diff --git a/Emby.Server.Implementations/Library/LibraryManager.cs b/Emby.Server.Implementations/Library/LibraryManager.cs
index 0044fcd4dc..97e03b45c9 100644
--- a/Emby.Server.Implementations/Library/LibraryManager.cs
+++ b/Emby.Server.Implementations/Library/LibraryManager.cs
@@ -2332,7 +2332,10 @@ namespace Emby.Server.Implementations.Library
         {
             IOrderedEnumerable<BaseItem>? orderedItems = null;
 
-            foreach (var orderBy in sortBy.Select(o => GetComparer(o, user)).Where(c => c is not null))
+            var comparers = sortBy.Select(o => GetComparer(o, user)).Where(c => c is not null).ToList();
+            items = PrefetchUserData(items, user, comparers);
+
+            foreach (var orderBy in comparers)
             {
                 if (orderBy is RandomComparer)
                 {
@@ -2364,14 +2367,14 @@ namespace Emby.Server.Implementations.Library
         {
             IOrderedEnumerable<BaseItem>? orderedItems = null;
 
-            foreach (var (name, sortOrder) in orderBy)
-            {
-                var comparer = GetComparer(name, user);
-                if (comparer is null)
-                {
-                    continue;
-                }
+            var comparers = orderBy
+                .Select(o => (Comparer: GetComparer(o.OrderBy, user), o.SortOrder))
+                .Where(c => c.Comparer is not null)
+                .ToList();
+            items = PrefetchUserData(items, user, comparers.Select(c => c.Comparer).ToList());
 
+            foreach (var (comparer, sortOrder) in comparers)
+            {
                 if (comparer is RandomComparer)
                 {
                     var randomItems = items.ToArray();
@@ -2397,6 +2400,31 @@ namespace Emby.Server.Implementations.Library
             return orderedItems ?? items;
         }
 
+        // The user comparers read user data per item, so without one batched read up front an
+        // in-memory sort would issue a database round trip per comparison.
+        private IEnumerable<BaseItem> PrefetchUserData(IEnumerable<BaseItem> items, User? user, IReadOnlyList<IBaseItemComparer?> comparers)
+        {
+            if (user is null)
+            {
+                return items;
+            }
+
+            var userComparers = comparers.OfType<IUserBaseItemComparer>().ToList();
+            if (userComparers.Count == 0)
+            {
+                return items;
+            }
+
+            var itemList = items as IReadOnlyList<BaseItem> ?? items.ToList();
+            var userData = _userDataManager.GetUserDataBatch(itemList, user);
+            foreach (var comparer in userComparers)
+            {
+                comparer.PrefetchedUserData = userData;
+            }
+
+            return itemList;
+        }
+
         /// <summary>
         /// Gets the comparer.
         /// </summary>
diff --git a/Emby.Server.Implementations/Library/UserDataManager.cs b/Emby.Server.Implementations/Library/UserDataManager.cs
index 0680046c11..4ddbd60671 100644
--- a/Emby.Server.Implementations/Library/UserDataManager.cs
+++ b/Emby.Server.Implementations/Library/UserDataManager.cs
@@ -2,10 +2,8 @@
 
 using System;
 using System.Collections.Generic;
-using System.Globalization;
 using System.Linq;
 using System.Threading;
-using BitFaster.Caching.Lru;
 using Jellyfin.Database.Implementations;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Configuration;
@@ -27,7 +25,6 @@ namespace Emby.Server.Implementations.Library
     {
         private readonly IServerConfigurationManager _config;
         private readonly IDbContextFactory<JellyfinDbContext> _repository;
-        private readonly FastConcurrentLru<string, UserItemData> _cache;
 
         /// <summary>
         /// Initializes a new instance of the <see cref="UserDataManager"/> class.
@@ -40,7 +37,6 @@ namespace Emby.Server.Implementations.Library
         {
             _config = config;
             _repository = repository;
-            _cache = new FastConcurrentLru<string, UserItemData>(Environment.ProcessorCount, _config.Configuration.CacheSize, StringComparer.OrdinalIgnoreCase);
         }
 
         /// <inheritdoc />
@@ -77,11 +73,6 @@ namespace Emby.Server.Implementations.Library
             dbContext.SaveChanges();
             transaction.Commit();
 
-            var userId = user.InternalId;
-            var cacheKey = GetCacheKey(userId, item.Id);
-            _cache.AddOrUpdate(cacheKey, userData);
-            item.UserData = dbContext.UserData.Where(e => e.ItemId == item.Id).AsNoTracking().ToArray(); // rehydrate the cached userdata
-
             UserDataSaved?.Invoke(this, new UserDataSaveEventArgs
             {
                 Keys = keys,
@@ -180,64 +171,41 @@ namespace Emby.Server.Implementations.Library
         /// <inheritdoc />
         public Dictionary<Guid, UserItemData> GetUserDataBatch(IReadOnlyList<BaseItem> items, User user)
         {
+            ArgumentNullException.ThrowIfNull(items);
+            ArgumentNullException.ThrowIfNull(user);
+
             var result = new Dictionary<Guid, UserItemData>(items.Count);
-            var itemsNeedingQuery = new List<(BaseItem Item, List<string> Keys)>();
-
-            foreach (var item in items)
-            {
-                var cacheKey = GetCacheKey(user.InternalId, item.Id);
-                if (_cache.TryGet(cacheKey, out var cachedData))
-                {
-                    result[item.Id] = cachedData;
-                }
-                else
-                {
-                    var userDataRow = ResolveUserDataRow(item, item.UserData?.Where(e => e.UserId.Equals(user.Id)));
-                    var userData = userDataRow is not null ? Map(userDataRow) : null;
-                    if (userData is not null)
-                    {
-                        result[item.Id] = userData;
-                        _cache.AddOrUpdate(cacheKey, userData);
-                    }
-                    else
-                    {
-                        var keys = item.GetUserDataKeys();
-                        itemsNeedingQuery.Add((item, keys));
-                    }
-                }
-            }
-
-            if (itemsNeedingQuery.Count == 0)
+            if (items.Count == 0)
             {
                 return result;
             }
 
-            // Build a single query for all missing items. Fetch rows by item alone so rows kept
-            // under keys from older metadata resolve the same way as the in-memory path.
-            var allItemIds = itemsNeedingQuery.Select(x => x.Item.Id).ToList();
+            // Fetch rows by item alone so rows kept under keys from older metadata resolve the same
+            // way as the single item path.
+            var itemIds = items.Select(e => e.Id).Distinct().ToList();
             using var context = _repository.CreateDbContext();
-            var userDataArray = context.UserData
+            var userDataByItem = context.UserData
                 .AsNoTracking()
                 .Where(e => e.UserId.Equals(user.Id))
-                .WhereOneOrMany(allItemIds, e => e.ItemId)
-                .ToArray();
+                .WhereOneOrMany(itemIds, e => e.ItemId)
+                .ToArray()
+                .GroupBy(e => e.ItemId)
+                .ToDictionary(g => g.Key, g => g.ToArray());
 
-            var userDataByItem = userDataArray.GroupBy(e => e.ItemId).ToDictionary(g => g.Key, g => g.ToArray());
-            foreach (var (item, keys) in itemsNeedingQuery)
+            foreach (var item in items)
             {
-                UserItemData userData;
-                if (userDataByItem.TryGetValue(item.Id, out var itemUserData) && itemUserData.Length > 0)
+                if (result.ContainsKey(item.Id))
                 {
-                    userData = Map(ResolveUserDataRow(item, itemUserData)!);
-                }
-                else
-                {
-                    userData = new UserItemData { Key = keys.Count > 0 ? keys[0] : string.Empty };
+                    continue;
                 }
 
-                result[item.Id] = userData;
-                var cacheKey = GetCacheKey(user.InternalId, item.Id);
-                _cache.AddOrUpdate(cacheKey, userData);
+                var row = userDataByItem.TryGetValue(item.Id, out var itemUserData)
+                    ? ResolveUserDataRow(item, itemUserData)
+                    : null;
+
+                result[item.Id] = row is not null
+                    ? Map(row)
+                    : new UserItemData { Key = item.GetUserDataKeys().FirstOrDefault() ?? string.Empty };
             }
 
             return result;
@@ -340,20 +308,19 @@ namespace Emby.Server.Implementations.Library
             return result;
         }
 
-        /// <summary>
-        /// Gets the internal key.
-        /// </summary>
-        /// <returns>System.String.</returns>
-        private static string GetCacheKey(long internalUserId, Guid itemId)
-        {
-            return internalUserId.ToString(CultureInfo.InvariantCulture) + "-" + itemId.ToString("N", CultureInfo.InvariantCulture);
-        }
-
         /// <inheritdoc />
         public UserItemData? GetUserData(User user, BaseItem item)
         {
             ArgumentNullException.ThrowIfNull(user);
-            var row = ResolveUserDataRow(item, item.UserData?.Where(e => e.UserId.Equals(user.Id)));
+            ArgumentNullException.ThrowIfNull(item);
+
+            using var dbContext = _repository.CreateDbContext();
+            var rows = dbContext.UserData
+                .AsNoTracking()
+                .Where(e => e.ItemId == item.Id && e.UserId == user.Id)
+                .ToArray();
+
+            var row = ResolveUserDataRow(item, rows);
             return row is not null ? Map(row) : new UserItemData()
             {
                 Key = item.GetUserDataKeys()[0],
@@ -536,16 +503,6 @@ namespace Emby.Server.Implementations.Library
             }
 
             dbContext.SaveChanges();
-
-            var cacheKey = GetCacheKey(user.InternalId, item.Id);
-            if (_cache.TryGet(cacheKey, out var cached))
-            {
-                cached.AudioStreamIndex = null;
-                cached.SubtitleStreamIndex = null;
-                _cache.AddOrUpdate(cacheKey, cached);
-            }
-
-            item.UserData = dbContext.UserData.Where(e => e.ItemId == item.Id).AsNoTracking().ToArray();
         }
     }
 }
diff --git a/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs b/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
index 2c8e2b37d0..917485b457 100644
--- a/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/DatePlayedComparer.cs
@@ -1,6 +1,7 @@
 #nullable disable
 
 using System;
+using System.Collections.Generic;
 using Jellyfin.Data.Enums;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Entities;
@@ -27,6 +28,12 @@ namespace Emby.Server.Implementations.Sorting
         /// <value>The user manager.</value>
         public IUserManager UserManager { get; set; }
 
+        /// <summary>
+        /// Gets or sets the prefetched user data.
+        /// </summary>
+        /// <value>The prefetched user data.</value>
+        public IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData { get; set; }
+
         /// <summary>
         /// Gets or sets the user data manager.
         /// </summary>
@@ -57,7 +64,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <returns>DateTime.</returns>
         private DateTime GetDate(BaseItem x)
         {
-            var userdata = UserDataManager.GetUserData(User, x);
+            var userdata = this.GetUserData(x);
 
             if (userdata is not null && userdata.LastPlayedDate.HasValue)
             {
diff --git a/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs b/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
index 86d08ed27b..9eafca1391 100644
--- a/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsFavoriteOrLikeComparer.cs
@@ -1,6 +1,8 @@
 #nullable disable
 #pragma warning disable CS1591
 
+using System;
+using System.Collections.Generic;
 using Jellyfin.Data.Enums;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Entities;
@@ -35,6 +37,12 @@ namespace Emby.Server.Implementations.Sorting
         /// <value>The user manager.</value>
         public IUserManager UserManager { get; set; }
 
+        /// <summary>
+        /// Gets or sets the prefetched user data.
+        /// </summary>
+        /// <value>The prefetched user data.</value>
+        public IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData { get; set; }
+
         /// <summary>
         /// Compares the specified x.
         /// </summary>
@@ -53,7 +61,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <returns>DateTime.</returns>
         private int GetValue(BaseItem x)
         {
-            return x.IsFavoriteOrLiked(User, userItemData: null) ? 0 : 1;
+            return x.IsFavoriteOrLiked(User, this.GetUserData(x)) ? 0 : 1;
         }
     }
 }
diff --git a/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs b/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
index 9faa02f1fd..b4e3787ffc 100644
--- a/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsPlayedComparer.cs
@@ -2,6 +2,8 @@
 
 #pragma warning disable CS1591
 
+using System;
+using System.Collections.Generic;
 using Jellyfin.Data.Enums;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Entities;
@@ -36,6 +38,12 @@ namespace Emby.Server.Implementations.Sorting
         /// <value>The user manager.</value>
         public IUserManager UserManager { get; set; }
 
+        /// <summary>
+        /// Gets or sets the prefetched user data.
+        /// </summary>
+        /// <value>The prefetched user data.</value>
+        public IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData { get; set; }
+
         /// <summary>
         /// Compares the specified x.
         /// </summary>
@@ -54,7 +62,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <returns>DateTime.</returns>
         private int GetValue(BaseItem x)
         {
-            return x.IsPlayed(User, userItemData: null) ? 0 : 1;
+            return x.IsPlayed(User, this.GetUserData(x)) ? 0 : 1;
         }
     }
 }
diff --git a/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs b/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
index 6f177c4637..3b27b8092a 100644
--- a/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
+++ b/Emby.Server.Implementations/Sorting/IsUnplayedComparer.cs
@@ -2,6 +2,8 @@
 
 #pragma warning disable CS1591
 
+using System;
+using System.Collections.Generic;
 using Jellyfin.Data.Enums;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Entities;
@@ -36,6 +38,12 @@ namespace Emby.Server.Implementations.Sorting
         /// <value>The user manager.</value>
         public IUserManager UserManager { get; set; }
 
+        /// <summary>
+        /// Gets or sets the prefetched user data.
+        /// </summary>
+        /// <value>The prefetched user data.</value>
+        public IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData { get; set; }
+
         /// <summary>
         /// Compares the specified x.
         /// </summary>
@@ -54,7 +62,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <returns>DateTime.</returns>
         private int GetValue(BaseItem x)
         {
-            return x.IsUnplayed(User, userItemData: null) ? 0 : 1;
+            return x.IsUnplayed(User, this.GetUserData(x)) ? 0 : 1;
         }
     }
 }
diff --git a/Emby.Server.Implementations/Sorting/PlayCountComparer.cs b/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
index 26e28b03bc..568e9e69f1 100644
--- a/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
+++ b/Emby.Server.Implementations/Sorting/PlayCountComparer.cs
@@ -1,5 +1,7 @@
 #nullable disable
 
+using System;
+using System.Collections.Generic;
 using Jellyfin.Data.Enums;
 using Jellyfin.Database.Implementations.Entities;
 using MediaBrowser.Controller.Entities;
@@ -38,6 +40,12 @@ namespace Emby.Server.Implementations.Sorting
         /// <value>The user manager.</value>
         public IUserManager UserManager { get; set; }
 
+        /// <summary>
+        /// Gets or sets the prefetched user data.
+        /// </summary>
+        /// <value>The prefetched user data.</value>
+        public IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData { get; set; }
+
         /// <summary>
         /// Compares the specified x.
         /// </summary>
@@ -56,7 +64,7 @@ namespace Emby.Server.Implementations.Sorting
         /// <returns>DateTime.</returns>
         private int GetValue(BaseItem x)
         {
-            var userdata = UserDataManager.GetUserData(User, x);
+            var userdata = this.GetUserData(x);
 
             return userdata is null ? 0 : userdata.PlayCount;
         }
diff --git a/Emby.Server.Implementations/TV/TVSeriesManager.cs b/Emby.Server.Implementations/TV/TVSeriesManager.cs
index 459ad1a17e..bc418b5c52 100644
--- a/Emby.Server.Implementations/TV/TVSeriesManager.cs
+++ b/Emby.Server.Implementations/TV/TVSeriesManager.cs
@@ -13,6 +13,7 @@ using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Dto;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Persistence;
 using MediaBrowser.Controller.TV;
 using MediaBrowser.Model.Querying;
 using Episode = MediaBrowser.Controller.Entities.TV.Episode;
@@ -124,53 +125,100 @@ namespace Emby.Server.Implementations.TV
 
             var batchResult = _libraryManager.GetNextUpEpisodesBatch(query, seriesKeys, includeSpecials, includeRewatching);
 
-            var nextUpList = new List<(DateTime LastWatchedDate, Episode Episode)>();
-
+            var results = new List<NextUpEpisodeBatchResult>(seriesKeys.Count);
             foreach (var seriesKey in seriesKeys)
             {
-                if (!batchResult.TryGetValue(seriesKey, out var result))
+                if (batchResult.TryGetValue(seriesKey, out var result))
                 {
-                    continue;
+                    results.Add(result);
                 }
+            }
 
-                var nextEpisode = DetermineNextEpisode(result, user, includeSpecials, request.EnableResumable, false);
+            // The selection below tests the played state of every episode it considers, so read the whole
+            // series batch in one query rather than one query per series.
+            var selectionCandidates = new List<BaseItem>();
+            foreach (var result in results)
+            {
+                AddCandidate(selectionCandidates, result.NextUp);
+                AddCandidate(selectionCandidates, result.LastWatched);
+                AddCandidate(selectionCandidates, result.NextPlayedForRewatching);
+                AddCandidate(selectionCandidates, result.LastWatchedForRewatching);
 
+                if (result.Specials is not null)
+                {
+                    selectionCandidates.AddRange(result.Specials);
+                }
+            }
+
+            var selectionUserData = _userDataManager.GetUserDataBatch(selectionCandidates, user);
+
+            var candidates = new List<NextUpCandidate>();
+            foreach (var result in results)
+            {
+                var nextEpisode = SelectNextEpisode(result, user, includeSpecials, includePlayed: false, selectionUserData);
                 if (nextEpisode is not null)
                 {
-                    // The last played date and the version that was actually played live on the version item's user data
-                    // The played state propagated to the sibling versions carries no date
-                    var (playedVersion, lastPlayedDate) = GetMostRecentlyPlayedVersion(result.LastWatched, user);
-                    nextEpisode = GetPreferredVersion(nextEpisode, result.LastWatched, playedVersion);
-
-                    DateTime lastWatchedDate = DateTime.MinValue;
-                    if (result.LastWatched is not null)
-                    {
-                        lastWatchedDate = lastPlayedDate ?? DateTime.MinValue.AddDays(1);
-                    }
-
-                    nextUpList.Add((lastWatchedDate, nextEpisode));
+                    candidates.Add(new NextUpCandidate(nextEpisode, result.LastWatched, !request.EnableResumable));
                 }
 
                 if (includeRewatching)
                 {
-                    var nextPlayedEpisode = DetermineNextEpisodeForRewatching(result, user, includeSpecials);
-
+                    var nextPlayedEpisode = SelectNextEpisode(result, user, includeSpecials, includePlayed: true, selectionUserData);
                     if (nextPlayedEpisode is not null)
                     {
-                        var (playedVersion, lastPlayedDate) = GetMostRecentlyPlayedVersion(result.LastWatchedForRewatching, user);
-                        nextPlayedEpisode = GetPreferredVersion(nextPlayedEpisode, result.LastWatchedForRewatching, playedVersion);
-
-                        DateTime rewatchLastWatchedDate = DateTime.MinValue;
-                        if (result.LastWatchedForRewatching is not null)
-                        {
-                            rewatchLastWatchedDate = lastPlayedDate ?? DateTime.MinValue.AddDays(1);
-                        }
-
-                        nextUpList.Add((rewatchLastWatchedDate, nextPlayedEpisode));
+                        // A rewatch suggestion is dropped once it has been resumed, whatever the request asked for.
+                        candidates.Add(new NextUpCandidate(nextPlayedEpisode, result.LastWatchedForRewatching, true));
                     }
                 }
             }
 
+            // The resume progress may live on an alternate version, so read every version in one query.
+            var episodeVersions = new List<BaseItem>();
+            foreach (var candidate in candidates)
+            {
+                if (candidate.DropWhenResumed)
+                {
+                    candidate.EpisodeVersions = candidate.Episode.GetAllVersions();
+                    episodeVersions.AddRange(candidate.EpisodeVersions);
+                }
+            }
+
+            if (episodeVersions.Count > 0)
+            {
+                var resumeUserData = _userDataManager.GetUserDataBatch(episodeVersions, user);
+                candidates.RemoveAll(candidate => candidate.EpisodeVersions
+                    .Any(version => GetUserData(user, version, resumeUserData)?.PlaybackPositionTicks > 0));
+            }
+
+            // The last played date and the version that was actually played live on the version item's user data
+            // The played state propagated to the sibling versions carries no date
+            var lastWatchedVersions = new List<BaseItem>();
+            foreach (var candidate in candidates)
+            {
+                if (candidate.LastWatched is Video lastWatchedVideo)
+                {
+                    candidate.LastWatchedVersions = lastWatchedVideo.GetAllVersions();
+                    lastWatchedVersions.AddRange(candidate.LastWatchedVersions);
+                }
+            }
+
+            var lastWatchedUserData = _userDataManager.GetUserDataBatch(lastWatchedVersions, user);
+
+            var nextUpList = new List<(DateTime LastWatchedDate, Episode Episode)>(candidates.Count);
+            foreach (var candidate in candidates)
+            {
+                var (playedVersion, lastPlayedDate) = GetMostRecentlyPlayedVersion(candidate.LastWatchedVersions, user, lastWatchedUserData);
+                var nextEpisode = GetPreferredVersion(candidate.Episode, candidate.LastWatched, playedVersion);
+
+                DateTime lastWatchedDate = DateTime.MinValue;
+                if (candidate.LastWatched is not null)
+                {
+                    lastWatchedDate = lastPlayedDate ?? DateTime.MinValue.AddDays(1);
+                }
+
+                nextUpList.Add((lastWatchedDate, nextEpisode));
+            }
+
             var sortedEpisodes = nextUpList
                 .OrderByDescending(x => x.LastWatchedDate)
                 .Select(x => (BaseItem)x.Episode);
@@ -178,12 +226,25 @@ namespace Emby.Server.Implementations.TV
             return GetResult(sortedEpisodes, request);
         }
 
-        private Episode? DetermineNextEpisode(
-            MediaBrowser.Controller.Persistence.NextUpEpisodeBatchResult result,
+        private static void AddCandidate(List<BaseItem> candidates, BaseItem? item)
+        {
+            if (item is not null)
+            {
+                candidates.Add(item);
+            }
+        }
+
+        private UserItemData? GetUserData(User user, BaseItem item, IReadOnlyDictionary<Guid, UserItemData> prefetchedUserData)
+            => prefetchedUserData.TryGetValue(item.Id, out var userData)
+                ? userData
+                : _userDataManager.GetUserData(user, item);
+
+        private Episode? SelectNextEpisode(
+            NextUpEpisodeBatchResult result,
             User user,
             bool includeSpecials,
-            bool includeResumable,
-            bool includePlayed)
+            bool includePlayed,
+            IReadOnlyDictionary<Guid, UserItemData> prefetchedUserData)
         {
             var nextEpisode = (includePlayed ? result.NextPlayedForRewatching : result.NextUp) as Episode;
             var lastWatchedEpisode = (includePlayed ? result.LastWatchedForRewatching : result.LastWatched) as Episode;
@@ -217,60 +278,41 @@ namespace Emby.Server.Implementations.TV
 
                     if (!includePlayed)
                     {
-                        sortedEpisodes = sortedEpisodes.Where(episode => _userDataManager.GetUserData(user, episode) is not { Played: true });
+                        sortedEpisodes = sortedEpisodes.Where(episode => GetUserData(user, episode, prefetchedUserData) is not { Played: true });
                     }
 
                     nextEpisode = sortedEpisodes.FirstOrDefault();
                 }
             }
 
-            if (nextEpisode is not null && !includeResumable)
-            {
-                // The resume progress may live on an alternate version
-                foreach (var version in nextEpisode.GetAllVersions())
-                {
-                    if (_userDataManager.GetUserData(user, version)?.PlaybackPositionTicks > 0)
-                    {
-                        return null;
-                    }
-                }
-            }
-
             return nextEpisode;
         }
 
-        private Episode? DetermineNextEpisodeForRewatching(
-            MediaBrowser.Controller.Persistence.NextUpEpisodeBatchResult result,
-            User user,
-            bool includeSpecials)
-        {
-            return DetermineNextEpisode(result, user, includeSpecials, includeResumable: false, includePlayed: true);
-        }
-
         /// <summary>
         /// Gets the version of the last watched episode that was actually played, together with its last played date.
         /// The version that was played carries the most recent LastPlayedDate.
         /// dates.
         /// </summary>
-        /// <param name="lastWatched">The last watched episode (any version).</param>
+        /// <param name="versions">The versions of the last watched episode.</param>
         /// <param name="user">The user.</param>
+        /// <param name="prefetchedUserData">User data read for every version up front.</param>
         /// <returns>The played version and its last played date.</returns>
-        private (Video? PlayedVersion, DateTime? LastPlayedDate) GetMostRecentlyPlayedVersion(BaseItem? lastWatched, User user)
+        private (Video? PlayedVersion, DateTime? LastPlayedDate) GetMostRecentlyPlayedVersion(
+            IReadOnlyList<Video> versions,
+            User user,
+            IReadOnlyDictionary<Guid, UserItemData> prefetchedUserData)
         {
-            if (lastWatched is not Video lastWatchedVideo)
+            if (versions.Count == 0)
             {
                 return (null, null);
             }
 
-            var versions = lastWatchedVideo.GetAllVersions();
-            var userDataByVersion = _userDataManager.GetUserDataBatch(versions, user);
-
             var playedVersion = VersionPlaybackSelector.SelectMostRecentlyPlayed(
                 versions,
-                version => userDataByVersion.GetValueOrDefault(version.Id),
+                version => GetUserData(user, version, prefetchedUserData),
                 data => data.LastPlayedDate.HasValue);
 
-            return (playedVersion, playedVersion is null ? null : userDataByVersion[playedVersion.Id].LastPlayedDate);
+            return (playedVersion, playedVersion is null ? null : GetUserData(user, playedVersion, prefetchedUserData)?.LastPlayedDate);
         }
 
         /// <summary>
@@ -346,5 +388,28 @@ namespace Emby.Server.Implementations.TV
                 totalCount,
                 items.ToArray());
         }
+
+        /// <summary>
+        /// An episode picked for Next Up, together with the versions its user data is read from.
+        /// </summary>
+        private sealed class NextUpCandidate
+        {
+            public NextUpCandidate(Episode episode, BaseItem? lastWatched, bool dropWhenResumed)
+            {
+                Episode = episode;
+                LastWatched = lastWatched;
+                DropWhenResumed = dropWhenResumed;
+            }
+
+            public Episode Episode { get; }
+
+            public BaseItem? LastWatched { get; }
+
+            public bool DropWhenResumed { get; }
+
+            public IReadOnlyList<Video> EpisodeVersions { get; set; } = [];
+
+            public IReadOnlyList<Video> LastWatchedVersions { get; set; } = [];
+        }
     }
 }
diff --git a/MediaBrowser.Controller/Entities/UserViewBuilder.cs b/MediaBrowser.Controller/Entities/UserViewBuilder.cs
index f9ad2d86e6..69ca1a351f 100644
--- a/MediaBrowser.Controller/Entities/UserViewBuilder.cs
+++ b/MediaBrowser.Controller/Entities/UserViewBuilder.cs
@@ -449,19 +449,26 @@ namespace MediaBrowser.Controller.Entities
             IUserDataManager userDataManager,
             ILibraryManager libraryManager)
         {
-            var filtered = items.Where(i => Filter(i, user, query, userDataManager, libraryManager));
+            var itemList = items as IReadOnlyList<BaseItem> ?? items.ToList();
+
+            // The user data checks below run per item, so read them all in one query up front.
+            var userDataBatch = user is not null && RequiresUserData(query)
+                ? userDataManager.GetUserDataBatch(itemList, user)
+                : null;
+
+            var filtered = itemList.Where(i => Filter(i, user, query, userDataManager, libraryManager, userDataBatch));
 
             if (query.IsPlayed.HasValue && user is not null)
             {
-                var itemList = filtered.ToList();
-                var folderIds = itemList.OfType<Folder>().Select(f => f.Id).ToList();
+                var filteredList = filtered.ToList();
+                var folderIds = filteredList.OfType<Folder>().Select(f => f.Id).ToList();
 
                 if (folderIds.Count > 0)
                 {
                     var counts = libraryManager.GetPlayedAndTotalCountBatch(folderIds, user);
                     var isPlayedValue = query.IsPlayed.Value;
 
-                    return itemList.Where(item =>
+                    return filteredList.Where(item =>
                     {
                         if (item is Folder)
                         {
@@ -473,7 +480,7 @@ namespace MediaBrowser.Controller.Entities
                     });
                 }
 
-                return itemList;
+                return filteredList;
             }
 
             return filtered;
@@ -515,12 +522,29 @@ namespace MediaBrowser.Controller.Entities
                 itemsArray);
         }
 
+        private static bool RequiresUserData(InternalItemsQuery query)
+            => query.IsLiked.HasValue
+                || query.IsFavoriteOrLiked.HasValue
+                || query.IsFavorite.HasValue
+                || query.IsResumable.HasValue
+                || query.IsPlayed.HasValue;
+
+        private static UserItemData GetUserData(
+            IUserDataManager userDataManager,
+            User user,
+            BaseItem item,
+            Dictionary<Guid, UserItemData> userDataBatch)
+            => userDataBatch is not null && userDataBatch.TryGetValue(item.Id, out var userData)
+                ? userData
+                : userDataManager.GetUserData(user, item);
+
         private static bool Filter(
             BaseItem item,
             User user,
             InternalItemsQuery query,
             IUserDataManager userDataManager,
-            ILibraryManager libraryManager)
+            ILibraryManager libraryManager,
+            Dictionary<Guid, UserItemData> userDataBatch)
         {
             if (!string.IsNullOrEmpty(query.NameStartsWith) && !item.SortName.StartsWith(query.NameStartsWith, StringComparison.InvariantCultureIgnoreCase))
             {
@@ -568,7 +592,7 @@ namespace MediaBrowser.Controller.Entities
 
             if (query.IsLiked.HasValue)
             {
-                userData = userDataManager.GetUserData(user, item);
+                userData = GetUserData(userDataManager, user, item, userDataBatch);
                 if (!userData.Likes.HasValue || userData.Likes != query.IsLiked.Value)
                 {
                     return false;
@@ -577,7 +601,7 @@ namespace MediaBrowser.Controller.Entities
 
             if (query.IsFavoriteOrLiked.HasValue)
             {
-                userData ??= userDataManager.GetUserData(user, item);
+                userData ??= GetUserData(userDataManager, user, item, userDataBatch);
                 var isFavoriteOrLiked = userData.IsFavorite || (userData.Likes ?? false);
 
                 if (isFavoriteOrLiked != query.IsFavoriteOrLiked.Value)
@@ -588,7 +612,7 @@ namespace MediaBrowser.Controller.Entities
 
             if (query.IsFavorite.HasValue)
             {
-                userData ??= userDataManager.GetUserData(user, item);
+                userData ??= GetUserData(userDataManager, user, item, userDataBatch);
                 if (userData.IsFavorite != query.IsFavorite.Value)
                 {
                     return false;
@@ -597,7 +621,7 @@ namespace MediaBrowser.Controller.Entities
 
             if (query.IsResumable.HasValue)
             {
-                userData ??= userDataManager.GetUserData(user, item);
+                userData ??= GetUserData(userDataManager, user, item, userDataBatch);
                 var isResumable = userData.PlaybackPositionTicks > 0;
 
                 if (isResumable != query.IsResumable.Value)
@@ -612,7 +636,7 @@ namespace MediaBrowser.Controller.Entities
                 // Folders are batch-filtered by the collection Filter() overload.
                 if (!item.IsFolder)
                 {
-                    userData ??= userDataManager.GetUserData(user, item);
+                    userData ??= GetUserData(userDataManager, user, item, userDataBatch);
                     if (item.IsPlayed(user, userData) != query.IsPlayed.Value)
                     {
                         return false;
diff --git a/MediaBrowser.Controller/Sorting/IUserBaseItemComparer.cs b/MediaBrowser.Controller/Sorting/IUserBaseItemComparer.cs
index 2206a021a8..a402779eaa 100644
--- a/MediaBrowser.Controller/Sorting/IUserBaseItemComparer.cs
+++ b/MediaBrowser.Controller/Sorting/IUserBaseItemComparer.cs
@@ -1,6 +1,9 @@
 #nullable disable
 
+using System;
+using System.Collections.Generic;
 using Jellyfin.Database.Implementations.Entities;
+using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Library;
 
 namespace MediaBrowser.Controller.Sorting
@@ -27,5 +30,16 @@ namespace MediaBrowser.Controller.Sorting
         /// </summary>
         /// <value>The user data repository.</value>
         IUserDataManager UserDataManager { get; set; }
+
+        /// <summary>
+        /// Gets or sets user data for the items being sorted, keyed by item id, read once up front.
+        /// A comparer that does not store it reads its user data one item at a time instead.
+        /// </summary>
+        /// <value>The prefetched user data, or <c>null</c> when none was prefetched.</value>
+        IReadOnlyDictionary<Guid, UserItemData> PrefetchedUserData
+        {
+            get => null;
+            set { }
+        }
     }
 }
diff --git a/MediaBrowser.Controller/Sorting/UserBaseItemComparerExtensions.cs b/MediaBrowser.Controller/Sorting/UserBaseItemComparerExtensions.cs
new file mode 100644
index 0000000000..c4fb395e4f
--- /dev/null
+++ b/MediaBrowser.Controller/Sorting/UserBaseItemComparerExtensions.cs
@@ -0,0 +1,28 @@
+#nullable disable
+
+using MediaBrowser.Controller.Entities;
+
+namespace MediaBrowser.Controller.Sorting
+{
+    /// <summary>
+    /// Helpers shared by the comparers that sort on user data.
+    /// </summary>
+    public static class UserBaseItemComparerExtensions
+    {
+        /// <summary>
+        /// Gets the user data for an item, preferring the batch the sort prefetched.
+        /// </summary>
+        /// <param name="comparer">The comparer.</param>
+        /// <param name="item">The item.</param>
+        /// <returns>The item's user data.</returns>
+        public static UserItemData GetUserData(this IUserBaseItemComparer comparer, BaseItem item)
+        {
+            if (comparer.PrefetchedUserData is not null && comparer.PrefetchedUserData.TryGetValue(item.Id, out var userData))
+            {
+                return userData;
+            }
+
+            return comparer.UserDataManager.GetUserData(comparer.User, item);
+        }
+    }
+}
diff --git a/src/Jellyfin.LiveTv/Channels/ChannelManager.cs b/src/Jellyfin.LiveTv/Channels/ChannelManager.cs
index ed02fe6a1d..c0fef94f0b 100644
--- a/src/Jellyfin.LiveTv/Channels/ChannelManager.cs
+++ b/src/Jellyfin.LiveTv/Channels/ChannelManager.cs
@@ -212,7 +212,8 @@ namespace Jellyfin.LiveTv.Channels
             if (query.IsFavorite.HasValue)
             {
                 var val = query.IsFavorite.Value;
-                channels = channels.Where(i => _userDataManager.GetUserData(user, i).IsFavorite == val)
+                var userData = _userDataManager.GetUserDataBatch(channels, user);
+                channels = channels.Where(i => userData.TryGetValue(i.Id, out var data) && data.IsFavorite == val)
                     .ToList();
             }
 
diff --git a/src/Jellyfin.LiveTv/LiveTvManager.cs b/src/Jellyfin.LiveTv/LiveTvManager.cs
index 2edf7681db..ed389d9da0 100644
--- a/src/Jellyfin.LiveTv/LiveTvManager.cs
+++ b/src/Jellyfin.LiveTv/LiveTvManager.cs
@@ -304,8 +304,17 @@ namespace Jellyfin.LiveTv
 
             if (query.IsAiring ?? false)
             {
+                // Scoring reads the channel's user data per program, so read every channel's in one query.
+                var channels = programList
+                    .Cast<LiveTvProgram>()
+                    .Select(i => _libraryManager.GetItemById(i.ChannelId))
+                    .OfType<BaseItem>()
+                    .DistinctBy(i => i.Id)
+                    .ToList();
+                var channelUserData = _userDataManager.GetUserDataBatch(channels, user);
+
                 orderedPrograms = orderedPrograms
-                    .ThenByDescending(i => GetRecommendationScore(i, user, true));
+                    .ThenByDescending(i => GetRecommendationScore(i, user, true, channelUserData));
             }
 
             IEnumerable<BaseItem> programs = orderedPrograms;
@@ -338,7 +347,11 @@ namespace Jellyfin.LiveTv
                 _dtoService.GetBaseItemDtos(internalResult.Items, options, query.User)));
         }
 
-        private int GetRecommendationScore(LiveTvProgram program, User user, bool factorChannelWatchCount)
+        private int GetRecommendationScore(
+            LiveTvProgram program,
+            User user,
+            bool factorChannelWatchCount,
+            IReadOnlyDictionary<Guid, UserItemData> channelUserData)
         {
             var score = 0;
 
@@ -359,7 +372,9 @@ namespace Jellyfin.LiveTv
                 return score;
             }
 
-            var channelUserdata = _userDataManager.GetUserData(user, channel);
+            var channelUserdata = channelUserData.TryGetValue(channel.Id, out var cached)
+                ? cached
+                : _userDataManager.GetUserData(user, channel);
 
             if (channelUserdata.Likes.HasValue)
             {
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/LibraryManagerSortTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/LibraryManagerSortTests.cs
index 65ec41291d..bafbba7a60 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Library/LibraryManagerSortTests.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/LibraryManagerSortTests.cs
@@ -7,6 +7,7 @@ using Emby.Naming.Common;
 using Emby.Server.Implementations.Library;
 using Emby.Server.Implementations.Sorting;
 using Jellyfin.Data.Enums;
+using Jellyfin.Database.Implementations.Entities;
 using Jellyfin.Database.Implementations.Enums;
 using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Entities;
@@ -63,13 +64,49 @@ public class LibraryManagerSortTests
         Assert.Equal(new[] { "Alpha", "Mike", "Zulu" }, sorted.Select(i => i.Name));
     }
 
+    [Fact]
+    public void Sort_ComparerThatIgnoresPrefetchedUserData_StillSortsFromLiveReads()
+    {
+        var alpha = new Audio { Name = "Alpha", SortName = "Alpha", Id = Guid.NewGuid() };
+        var zulu = new Audio { Name = "Zulu", SortName = "Zulu", Id = Guid.NewGuid() };
+        var playCounts = new Dictionary<Guid, int> { [alpha.Id] = 1, [zulu.Id] = 9 };
+
+        var userDataManager = new Mock<IUserDataManager>();
+        userDataManager
+            .Setup(u => u.GetUserData(It.IsAny<User>(), It.IsAny<BaseItem>()))
+            .Returns<User, BaseItem>((_, item) => new UserItemData { Key = item.Id.ToString("N"), PlayCount = playCounts[item.Id] });
+        userDataManager
+            .Setup(u => u.GetUserDataBatch(It.IsAny<IReadOnlyList<BaseItem>>(), It.IsAny<User>()))
+            .Returns(new Dictionary<Guid, UserItemData>());
+
+        var libraryManager = CreateLibraryManager(
+            new IBaseItemComparer[] { new PluginPlayCountComparer() },
+            userDataManager);
+
+        var sorted = libraryManager.Sort(
+            new BaseItem[] { alpha, zulu },
+            new User("sorter", "provider", "provider"),
+            new[] { (ItemSortBy.PlayCount, SortOrder.Descending) }).ToArray();
+
+        Assert.Equal(new[] { "Zulu", "Alpha" }, sorted.Select(i => i.Name));
+        userDataManager.Verify(u => u.GetUserData(It.IsAny<User>(), It.IsAny<BaseItem>()), Times.AtLeastOnce);
+    }
+
     private static Folder MakeFolder(string name, DateTime dateLastMediaAdded)
         => new() { Name = name, Id = Guid.NewGuid(), DateLastMediaAdded = dateLastMediaAdded };
 
-    private static Emby.Server.Implementations.Library.LibraryManager CreateLibraryManager(IReadOnlyCollection<IBaseItemComparer> comparers)
+    private static Emby.Server.Implementations.Library.LibraryManager CreateLibraryManager(
+        IReadOnlyCollection<IBaseItemComparer> comparers,
+        Mock<IUserDataManager>? userDataManager = null)
     {
         var fixture = new Fixture().Customize(new AutoMoqCustomization());
         fixture.Register(() => new NamingOptions());
+
+        if (userDataManager is not null)
+        {
+            fixture.Inject(userDataManager.Object);
+        }
+
         var configMock = fixture.Freeze<Mock<IServerConfigurationManager>>();
         configMock.Setup(c => c.ApplicationPaths.ProgramDataPath).Returns("/data");
         BaseItem.ConfigurationManager ??= configMock.Object;
@@ -86,4 +123,22 @@ public class LibraryManagerSortTests
                 fixture.Create<IEnumerable<ILibraryPostScanTask>>()))
             .Create();
     }
+
+    /// <summary>
+    /// A comparer of the shape a third-party plugin ships: it implements
+    /// <see cref="IUserBaseItemComparer"/> without ever mentioning PrefetchedUserData.
+    /// </summary>
+    public sealed class PluginPlayCountComparer : IUserBaseItemComparer
+    {
+        public User User { get; set; } = null!;
+
+        public IUserManager UserManager { get; set; } = null!;
+
+        public IUserDataManager UserDataManager { get; set; } = null!;
+
+        public ItemSortBy Type => ItemSortBy.PlayCount;
+
+        public int Compare(BaseItem? x, BaseItem? y)
+            => UserDataManager.GetUserData(User, x!)!.PlayCount.CompareTo(UserDataManager.GetUserData(User, y!)!.PlayCount);
+    }
 }
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/UserDataManagerTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/UserDataManagerTests.cs
index ba3127bc08..6810ba64de 100644
--- a/tests/Jellyfin.Server.Implementations.Tests/Library/UserDataManagerTests.cs
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/UserDataManagerTests.cs
@@ -1,5 +1,4 @@
 using System;
-using System.Collections.Generic;
 using Emby.Server.Implementations.Library;
 using Jellyfin.Database.Implementations;
 using Jellyfin.Database.Implementations.Entities;
@@ -49,6 +48,12 @@ public sealed class UserDataManagerTests : IDisposable
         {
             Id = Guid.NewGuid()
         };
+
+        using (var ctx = CreateDbContext())
+        {
+            ctx.Users.Add(_user);
+            ctx.SaveChanges();
+        }
     }
 
     public void Dispose()
@@ -78,6 +83,23 @@ public sealed class UserDataManagerTests : IDisposable
         };
     }
 
+    private void Seed(AudioBook item, params UserData[] rows)
+    {
+        using var ctx = CreateDbContext();
+        ctx.BaseItems.Add(new BaseItemEntity { Id = item.Id, Type = typeof(AudioBook).FullName! });
+        ctx.UserData.AddRange(rows);
+        ctx.SaveChanges();
+    }
+
+    private User CreateOtherUser()
+    {
+        var user = new User("other", "auth-provider", "reset-provider") { Id = Guid.NewGuid() };
+        using var ctx = CreateDbContext();
+        ctx.Users.Add(user);
+        ctx.SaveChanges();
+        return user;
+    }
+
     private UserData CreateUserDataRow(AudioBook item, string key, long positionTicks)
     {
         return new UserData
@@ -98,11 +120,10 @@ public sealed class UserDataManagerTests : IDisposable
         var currentKey = item.GetUserDataKeys()[0];
 
         // the retired-key row comes first to ensure selection is by key, not row order
-        item.UserData = new List<UserData>
-        {
+        Seed(
+            item,
             CreateUserDataRow(item, "Author-Old Album-0001Old File Name", 111),
-            CreateUserDataRow(item, currentKey, 222)
-        };
+            CreateUserDataRow(item, currentKey, 222));
 
         var userData = _userDataManager.GetUserData(_user, item);
 
@@ -117,11 +138,10 @@ public sealed class UserDataManagerTests : IDisposable
         var item = CreateAudioBook();
         var idKey = item.GetUserDataKeys()[1];
 
-        item.UserData = new List<UserData>
-        {
+        Seed(
+            item,
             CreateUserDataRow(item, "Author-Old Album-0001Old File Name", 111),
-            CreateUserDataRow(item, idKey, 333)
-        };
+            CreateUserDataRow(item, idKey, 333));
 
         var userData = _userDataManager.GetUserData(_user, item);
 
@@ -135,10 +155,7 @@ public sealed class UserDataManagerTests : IDisposable
     {
         var item = CreateAudioBook();
 
-        item.UserData = new List<UserData>
-        {
-            CreateUserDataRow(item, "Author-Old Album-0001Old File Name", 111)
-        };
+        Seed(item, CreateUserDataRow(item, "Author-Old Album-0001Old File Name", 111));
 
         var userData = _userDataManager.GetUserData(_user, item);
 
@@ -150,7 +167,7 @@ public sealed class UserDataManagerTests : IDisposable
     public void GetUserData_NoRows_ReturnsDefaultWithPrimaryKey()
     {
         var item = CreateAudioBook();
-        item.UserData = new List<UserData>();
+        Seed(item);
 
         var userData = _userDataManager.GetUserData(_user, item);
 
@@ -166,13 +183,9 @@ public sealed class UserDataManagerTests : IDisposable
         var currentKey = item.GetUserDataKeys()[0];
 
         var otherUserRow = CreateUserDataRow(item, currentKey, 999);
-        otherUserRow.UserId = Guid.NewGuid();
+        otherUserRow.UserId = CreateOtherUser().Id;
 
-        item.UserData = new List<UserData>
-        {
-            otherUserRow,
-            CreateUserDataRow(item, currentKey, 222)
-        };
+        Seed(item, otherUserRow, CreateUserDataRow(item, currentKey, 222));
 
         var userData = _userDataManager.GetUserData(_user, item);
 
@@ -183,23 +196,15 @@ public sealed class UserDataManagerTests : IDisposable
     [Fact]
     public void GetUserDataBatch_DatabaseFallback_ResolvesRowsByKeyOrder()
     {
-        // no preloaded navigation data, so the batch takes the database fallback
         var fossilItem = CreateAudioBook();
         var retiredItem = CreateAudioBook();
 
-        using (var ctx = CreateDbContext())
-        {
-            ctx.Users.Add(_user);
-            ctx.BaseItems.Add(new BaseItemEntity { Id = fossilItem.Id, Type = typeof(AudioBook).FullName! });
-            ctx.BaseItems.Add(new BaseItemEntity { Id = retiredItem.Id, Type = typeof(AudioBook).FullName! });
-
-            // the stale id-key row is inserted first so selection by row order would return it
-            ctx.UserData.AddRange(
-                CreateUserDataRow(fossilItem, fossilItem.GetUserDataKeys()[1], 111),
-                CreateUserDataRow(fossilItem, fossilItem.GetUserDataKeys()[0], 222),
-                CreateUserDataRow(retiredItem, "Author-Old Album-0001Old File Name", 333));
-            ctx.SaveChanges();
-        }
+        // the stale id-key row is inserted first so selection by row order would return it
+        Seed(
+            fossilItem,
+            CreateUserDataRow(fossilItem, fossilItem.GetUserDataKeys()[1], 111),
+            CreateUserDataRow(fossilItem, fossilItem.GetUserDataKeys()[0], 222));
+        Seed(retiredItem, CreateUserDataRow(retiredItem, "Author-Old Album-0001Old File Name", 333));
 
         var result = _userDataManager.GetUserDataBatch([fossilItem, retiredItem], _user);
 
diff --git a/tests/Jellyfin.Server.Implementations.Tests/TV/TVSeriesManagerNextUpTests.cs b/tests/Jellyfin.Server.Implementations.Tests/TV/TVSeriesManagerNextUpTests.cs
new file mode 100644
index 0000000000..a112e84519
--- /dev/null
+++ b/tests/Jellyfin.Server.Implementations.Tests/TV/TVSeriesManagerNextUpTests.cs
@@ -0,0 +1,94 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using Emby.Server.Implementations.TV;
+using Jellyfin.Database.Implementations.Entities;
+using MediaBrowser.Controller.Configuration;
+using MediaBrowser.Controller.Dto;
+using MediaBrowser.Controller.Entities;
+using MediaBrowser.Controller.Entities.TV;
+using MediaBrowser.Controller.Library;
+using MediaBrowser.Controller.Persistence;
+using MediaBrowser.Model.Configuration;
+using MediaBrowser.Model.Querying;
+using Moq;
+using Xunit;
+
+namespace Jellyfin.Server.Implementations.Tests.TV;
+
+public class TVSeriesManagerNextUpTests
+{
+    [Theory]
+    [InlineData(1)]
+    [InlineData(25)]
+    [InlineData(200)]
+    public void GetNextUp_ReadsUserDataInABoundedNumberOfQueries(int seriesCount)
+    {
+        var user = new User("next-up", "provider", "provider");
+        var libraryManager = new Mock<ILibraryManager>();
+        var userDataManager = new Mock<IUserDataManager>();
+
+        var seriesKeys = Enumerable.Range(0, seriesCount)
+            .Select(i => i.ToString(CultureInfo.InvariantCulture))
+            .ToList();
+
+        var batch = seriesKeys.ToDictionary(
+            key => key,
+            key => new NextUpEpisodeBatchResult
+            {
+                NextUp = new Episode { Id = Guid.NewGuid(), Name = "Next " + key },
+                LastWatched = new Episode { Id = Guid.NewGuid(), Name = "Watched " + key }
+            });
+
+        libraryManager
+            .Setup(l => l.GetNextUpSeriesKeys(It.IsAny<InternalItemsQuery>(), It.IsAny<IReadOnlyCollection<BaseItem>>(), It.IsAny<DateTime>()))
+            .Returns(seriesKeys);
+        libraryManager
+            .Setup(l => l.GetNextUpEpisodesBatch(It.IsAny<InternalItemsQuery>(), It.IsAny<IReadOnlyList<string>>(), It.IsAny<bool>(), It.IsAny<bool>()))
+            .Returns(batch);
+        libraryManager.Setup(l => l.GetLinkedAlternateVersions(It.IsAny<Video>())).Returns([]);
+        libraryManager.Setup(l => l.GetLocalAlternateVersionIds(It.IsAny<Video>())).Returns([]);
+
+        var batchReads = 0;
+        userDataManager
+            .Setup(u => u.GetUserDataBatch(It.IsAny<IReadOnlyList<BaseItem>>(), It.IsAny<User>()))
+            .Returns<IReadOnlyList<BaseItem>, User>((items, _) =>
+            {
+                batchReads++;
+                return items.DistinctBy(i => i.Id).ToDictionary(
+                    i => i.Id,
+                    i => new UserItemData { Key = i.Id.ToString("N", CultureInfo.InvariantCulture) });
+            });
+
+        var previousLibraryManager = BaseItem.LibraryManager;
+        BaseItem.LibraryManager = libraryManager.Object;
+
+        try
+        {
+            var manager = new TVSeriesManager(userDataManager.Object, libraryManager.Object, CreateConfigurationManager());
+
+            var result = manager.GetNextUp(
+                new NextUpQuery { User = user, EnableTotalRecordCount = true },
+                [],
+                new DtoOptions(false));
+
+            Assert.Equal(seriesCount, result.TotalRecordCount);
+
+            // Selection, the resume check and the last played date: three reads whatever the library holds.
+            Assert.Equal(3, batchReads);
+            userDataManager.Verify(u => u.GetUserData(It.IsAny<User>(), It.IsAny<BaseItem>()), Times.Never);
+        }
+        finally
+        {
+            BaseItem.LibraryManager = previousLibraryManager;
+        }
+    }
+
+    private static IServerConfigurationManager CreateConfigurationManager()
+    {
+        var configurationManager = new Mock<IServerConfigurationManager>();
+        configurationManager.SetupGet(c => c.Configuration).Returns(new ServerConfiguration());
+        return configurationManager.Object;
+    }
+}
diff --git a/tests/Jellyfin.Server.Tests/Library/UserDataManagerReplicaTests.cs b/tests/Jellyfin.Server.Tests/Library/UserDataManagerReplicaTests.cs
new file mode 100644
index 0000000000..75ac1bd0b9
--- /dev/null
+++ b/tests/Jellyfin.Server.Tests/Library/UserDataManagerReplicaTests.cs
@@ -0,0 +1,243 @@
+using System;
+using System.Collections.Generic;
+using System.Globalization;
+using System.Linq;
+using System.Threading;
+using System.Threading.Tasks;
+using Emby.Server.Implementations.Library;
+using Jellyfin.Database.Implementations;
+using Jellyfin.Database.Implementations.DbConfiguration;
+using Jellyfin.Database.Implementations.Entities;
+using Jellyfin.Database.Implementations.Locking;
+using Jellyfin.Database.Providers.PostgreSQL;
+using Jellyfin.Server.Tests.Migrations;
+using MediaBrowser.Controller.Configuration;
+using MediaBrowser.Model.Configuration;
+using MediaBrowser.Model.Entities;
+using Microsoft.EntityFrameworkCore;
+using Microsoft.Extensions.Logging.Abstractions;
+using Moq;
+using Npgsql;
+using Xunit;
+using AudioBook = MediaBrowser.Controller.Entities.AudioBook;
+
+namespace Jellyfin.Server.Tests.Library;
+
+/// <summary>
+/// Two independently constructed <see cref="UserDataManager"/> instances over one PostgreSQL database are the
+/// in-process stand-in for two replicas sharing one database: what either of them writes, the other has to
+/// see on its very next read, and a read-modify-write on one must not roll back the other's.
+/// </summary>
+[Trait("Category", "RequiresDocker")]
+public sealed class UserDataManagerReplicaTests : IClassFixture<UserDataManagerReplicaTests.DatabaseFixture>
+{
+    private static readonly long _quarterIn = TimeSpan.FromMinutes(20).Ticks;
+
+    private readonly NpgsqlDataSource _dataSource;
+
+    public UserDataManagerReplicaTests(DatabaseFixture fixture)
+    {
+        _dataSource = fixture.DataSource;
+    }
+
+    /// <summary>
+    /// A resume position written by the replica serving the playback tick has to be the position the next
+    /// request reads, whichever replica it lands on - both through the single item read the write path uses
+    /// and through the batch read the library pages render from.
+    /// </summary>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    [Fact]
+    public async Task ResumePositionWrittenOnOneReplica_IsReadOnAnother()
+    {
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var itemId = Guid.NewGuid();
+        var user = await CreateUserAndItemAsync(_dataSource, itemId, cancellationToken);
+
+        var replicaA = CreateManager(_dataSource);
+        var replicaB = CreateManager(_dataSource);
+        var itemOnA = new AudioBook { Id = itemId, Name = "Replica Book" };
+        var itemOnB = new AudioBook { Id = itemId, Name = "Replica Book" };
+
+        var early = replicaA.GetUserData(user, itemOnA)!;
+        early.PlaybackPositionTicks = TimeSpan.FromMinutes(5).Ticks;
+        replicaA.SaveUserData(user, itemOnA, early, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        // Replica B materialised the item before the later tick, so it holds the earlier row in memory.
+        itemOnB.UserData = await LoadUserDataAsync(_dataSource, itemId, cancellationToken);
+
+        var later = replicaA.GetUserData(user, itemOnA)!;
+        later.PlaybackPositionTicks = _quarterIn;
+        replicaA.SaveUserData(user, itemOnA, later, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        Assert.Equal(_quarterIn, replicaB.GetUserData(user, itemOnB)!.PlaybackPositionTicks);
+        Assert.Equal(_quarterIn, replicaB.GetUserDataBatch([itemOnB], user)[itemId].PlaybackPositionTicks);
+    }
+
+    /// <summary>
+    /// The playback tick is a read-modify-write of the whole row, so a tick served by one replica must build
+    /// on the favourite another replica just recorded instead of writing it back out.
+    /// </summary>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    [Fact]
+    public async Task PlaybackTickOnOneReplica_KeepsFavouriteSetOnAnother()
+    {
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var itemId = Guid.NewGuid();
+        var user = await CreateUserAndItemAsync(_dataSource, itemId, cancellationToken);
+
+        var replicaA = CreateManager(_dataSource);
+        var replicaB = CreateManager(_dataSource);
+        var itemOnA = new AudioBook { Id = itemId, Name = "Replica Book" };
+        var itemOnB = new AudioBook { Id = itemId, Name = "Replica Book" };
+
+        var seed = replicaA.GetUserData(user, itemOnA)!;
+        seed.PlaybackPositionTicks = TimeSpan.FromMinutes(5).Ticks;
+        replicaA.SaveUserData(user, itemOnA, seed, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        // Replica B is serving the playback session and read the item before the favourite was recorded.
+        itemOnB.UserData = await LoadUserDataAsync(_dataSource, itemId, cancellationToken);
+
+        var favourited = replicaA.GetUserData(user, itemOnA)!;
+        favourited.IsFavorite = true;
+        replicaA.SaveUserData(user, itemOnA, favourited, UserDataSaveReason.UpdateUserRating, cancellationToken);
+
+        var tick = replicaB.GetUserData(user, itemOnB)!;
+        tick.PlaybackPositionTicks = _quarterIn;
+        replicaB.SaveUserData(user, itemOnB, tick, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        var stored = replicaA.GetUserData(user, itemOnA)!;
+        Assert.True(stored.IsFavorite);
+        Assert.Equal(_quarterIn, stored.PlaybackPositionTicks);
+    }
+
+    /// <summary>
+    /// A tick that lands on the other replica has to carry the position forward from where the session
+    /// actually is, not from the position that replica happened to have in memory.
+    /// </summary>
+    /// <returns>A <see cref="Task"/> representing the asynchronous operation.</returns>
+    [Fact]
+    public async Task PlaybackTickOnOneReplica_ResumesFromThePositionAnotherWrote()
+    {
+        var cancellationToken = TestContext.Current.CancellationToken;
+        var itemId = Guid.NewGuid();
+        var user = await CreateUserAndItemAsync(_dataSource, itemId, cancellationToken);
+
+        var replicaA = CreateManager(_dataSource);
+        var replicaB = CreateManager(_dataSource);
+        var itemOnA = new AudioBook { Id = itemId, Name = "Replica Book" };
+        var itemOnB = new AudioBook { Id = itemId, Name = "Replica Book" };
+
+        var seed = replicaA.GetUserData(user, itemOnA)!;
+        seed.PlaybackPositionTicks = TimeSpan.FromMinutes(5).Ticks;
+        replicaA.SaveUserData(user, itemOnA, seed, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        itemOnB.UserData = await LoadUserDataAsync(_dataSource, itemId, cancellationToken);
+
+        // The viewer seeks forward and the tick reporting it lands on replica A.
+        var seeked = replicaA.GetUserData(user, itemOnA)!;
+        seeked.PlaybackPositionTicks = _quarterIn;
+        replicaA.SaveUserData(user, itemOnA, seeked, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        // The next tick lands on replica B, which adds ten seconds to whatever it reads.
+        var tick = replicaB.GetUserData(user, itemOnB)!;
+        tick.PlaybackPositionTicks += TimeSpan.FromSeconds(10).Ticks;
+        replicaB.SaveUserData(user, itemOnB, tick, UserDataSaveReason.PlaybackProgress, cancellationToken);
+
+        var stored = replicaA.GetUserData(user, itemOnA)!;
+        Assert.Equal(_quarterIn + TimeSpan.FromSeconds(10).Ticks, stored.PlaybackPositionTicks);
+    }
+
+    private static UserDataManager CreateManager(NpgsqlDataSource dataSource)
+    {
+        var config = new Mock<IServerConfigurationManager>();
+        config.SetupGet(c => c.Configuration).Returns(new ServerConfiguration());
+        return new UserDataManager(config.Object, new DataSourceContextFactory(dataSource));
+    }
+
+    private static async Task<ICollection<UserData>> LoadUserDataAsync(NpgsqlDataSource dataSource, Guid itemId, CancellationToken cancellationToken)
+    {
+        var context = CreateContext(dataSource);
+        await using (context.ConfigureAwait(false))
+        {
+            return await context.UserData
+                .AsNoTracking()
+                .Where(e => e.ItemId.Equals(itemId))
+                .ToArrayAsync(cancellationToken)
+                .ConfigureAwait(false);
+        }
+    }
+
+    private static async Task<User> CreateUserAndItemAsync(NpgsqlDataSource dataSource, Guid itemId, CancellationToken cancellationToken)
+    {
+        var context = CreateContext(dataSource);
+        await using (context.ConfigureAwait(false))
+        {
+            var user = new User("replica-user-" + itemId.ToString("N", CultureInfo.InvariantCulture), "provider", "provider");
+            context.Users.Add(user);
+            context.BaseItems.Add(new BaseItemEntity { Id = itemId, Type = typeof(AudioBook).FullName! });
+            await context.SaveChangesAsync(cancellationToken).ConfigureAwait(false);
+
+            return user;
+        }
+    }
+
+    private static JellyfinDbContext CreateContext(NpgsqlDataSource dataSource)
+    {
+        var optionsBuilder = new DbContextOptionsBuilder<JellyfinDbContext>();
+        var provider = new PostgreSqlDatabaseProvider(dataSource);
+        provider.Initialise(optionsBuilder, new DatabaseConfigurationOptions { DatabaseType = "PostgreSQL" });
+        return new JellyfinDbContext(
+            optionsBuilder.Options,
+            NullLogger<JellyfinDbContext>.Instance,
+            provider,
+            new NoLockBehavior(NullLogger<NoLockBehavior>.Instance));
+    }
+
+    /// <summary>
+    /// Hands every <see cref="UserDataManager"/> its own context over the one shared database, the way the
+    /// pooled factory does in the server.
+    /// </summary>
+    private sealed class DataSourceContextFactory : IDbContextFactory<JellyfinDbContext>
+    {
+        private readonly NpgsqlDataSource _dataSource;
+
+        public DataSourceContextFactory(NpgsqlDataSource dataSource)
+        {
+            _dataSource = dataSource;
+        }
+
+        public JellyfinDbContext CreateDbContext() => CreateContext(_dataSource);
+    }
+
+    /// <summary>
+    /// Builds the schema once for the whole class. Every test keeps to its own user and item, so one
+    /// database serves all of them and the shared server is spared three schema builds.
+    /// </summary>
+    public sealed class DatabaseFixture : IAsyncLifetime
+    {
+        private PostgreSqlTestServer _server = null!;
+
+        public NpgsqlDataSource DataSource { get; private set; } = null!;
+
+        /// <inheritdoc/>
+        public async ValueTask InitializeAsync()
+        {
+            _server = await PostgreSqlTestServer.StartAsync().ConfigureAwait(false);
+            var connectionString = await _server.CreateDatabaseAsync("userdata_replica", CancellationToken.None).ConfigureAwait(false);
+            DataSource = new NpgsqlDataSourceBuilder(connectionString).Build();
+
+            var context = CreateContext(DataSource);
+            await using (context.ConfigureAwait(false))
+            {
+                await context.Database.EnsureCreatedAsync(CancellationToken.None).ConfigureAwait(false);
+            }
+        }
+
+        /// <inheritdoc/>
+        public async ValueTask DisposeAsync()
+        {
+            await DataSource.DisposeAsync().ConfigureAwait(false);
+            await _server.DisposeAsync().ConfigureAwait(false);
+        }
+    }
+}