diff --git a/Emby.Dlna/PlayTo/PlayToController.cs b/Emby.Dlna/PlayTo/PlayToController.cs
index 23f2456ac..e147cb977 100644
--- a/Emby.Dlna/PlayTo/PlayToController.cs
+++ b/Emby.Dlna/PlayTo/PlayToController.cs
@@ -569,7 +569,7 @@ namespace Emby.Dlna.PlayTo
                         streamInfo.TargetVideoCodecTag,
                         streamInfo.IsTargetAVC);
 
-                return list.Count == 0 ? null : list[0];
+                return list.FirstOrDefault();
             }
 
             return null;
@@ -883,7 +883,7 @@ namespace Emby.Dlna.PlayTo
 
         private class StreamParams
         {
-            private MediaSourceInfo mediaSource;
+            private MediaSourceInfo _mediaSource;
             private IMediaSourceManager _mediaSourceManager;
 
             public Guid ItemId { get; set; }
@@ -908,24 +908,22 @@ namespace Emby.Dlna.PlayTo
 
             public async Task<MediaSourceInfo> GetMediaSource(CancellationToken cancellationToken)
             {
-                if (mediaSource != null)
+                if (_mediaSource != null)
                 {
-                    return mediaSource;
+                    return _mediaSource;
                 }
 
-                var hasMediaSources = Item as IHasMediaSources;
-
-                if (hasMediaSources == null)
+                if (Item is not IHasMediaSources)
                 {
                     return null;
                 }
 
                 if (_mediaSourceManager != null)
                 {
-                    mediaSource = await _mediaSourceManager.GetMediaSource(Item, MediaSourceId, LiveStreamId, false, cancellationToken).ConfigureAwait(false);
+                    _mediaSource = await _mediaSourceManager.GetMediaSource(Item, MediaSourceId, LiveStreamId, false, cancellationToken).ConfigureAwait(false);
                 }
 
-                return mediaSource;
+                return _mediaSource;
             }
 
             private static Guid GetItemId(string url)
diff --git a/Emby.Server.Implementations/Data/SqliteItemRepository.cs b/Emby.Server.Implementations/Data/SqliteItemRepository.cs
index 1da9b4650..662bca508 100644
--- a/Emby.Server.Implementations/Data/SqliteItemRepository.cs
+++ b/Emby.Server.Implementations/Data/SqliteItemRepository.cs
@@ -5914,7 +5914,7 @@ AND Type = @InternalPersonType)");
             }
         }
 
-        public void SaveMediaStreams(Guid id, List<MediaStream> streams, CancellationToken cancellationToken)
+        public void SaveMediaStreams(Guid id, IReadOnlyList<MediaStream> streams, CancellationToken cancellationToken)
         {
             CheckDisposed();
 
@@ -5946,7 +5946,7 @@ AND Type = @InternalPersonType)");
             }
         }
 
-        private void InsertMediaStreams(byte[] idBlob, List<MediaStream> streams, IDatabaseConnection db)
+        private void InsertMediaStreams(byte[] idBlob, IReadOnlyList<MediaStream> streams, IDatabaseConnection db)
         {
             const int Limit = 10;
             var startIndex = 0;
diff --git a/Emby.Server.Implementations/IO/ManagedFileSystem.cs b/Emby.Server.Implementations/IO/ManagedFileSystem.cs
index 5c86dbbb7..4f8a52f41 100644
--- a/Emby.Server.Implementations/IO/ManagedFileSystem.cs
+++ b/Emby.Server.Implementations/IO/ManagedFileSystem.cs
@@ -581,7 +581,7 @@ namespace Emby.Server.Implementations.IO
         }
 
         /// <inheritdoc />
-        public virtual List<FileSystemMetadata> GetDrives()
+        public virtual IEnumerable<FileSystemMetadata> GetDrives()
         {
             // check for ready state to avoid waiting for drives to timeout
             // some drives on linux have no actual size or are used for other purposes
@@ -595,7 +595,7 @@ namespace Emby.Server.Implementations.IO
                     Name = d.Name,
                     FullName = d.RootDirectory.FullName,
                     IsDirectory = true
-                }).ToList();
+                });
         }
 
         /// <inheritdoc />
diff --git a/Emby.Server.Implementations/Library/MediaSourceManager.cs b/Emby.Server.Implementations/Library/MediaSourceManager.cs
index a414e7e16..eb95977ef 100644
--- a/Emby.Server.Implementations/Library/MediaSourceManager.cs
+++ b/Emby.Server.Implementations/Library/MediaSourceManager.cs
@@ -344,7 +344,7 @@ namespace Emby.Server.Implementations.Library
             return sources;
         }
 
-        private string[] NormalizeLanguage(string language)
+        private IReadOnlyList<string> NormalizeLanguage(string language)
         {
             if (string.IsNullOrEmpty(language))
             {
diff --git a/Emby.Server.Implementations/Library/MediaStreamSelector.cs b/Emby.Server.Implementations/Library/MediaStreamSelector.cs
index da0c89c13..c5abb9a0a 100644
--- a/Emby.Server.Implementations/Library/MediaStreamSelector.cs
+++ b/Emby.Server.Implementations/Library/MediaStreamSelector.cs
@@ -1,5 +1,3 @@
-#nullable disable
-
 #pragma warning disable CS1591
 
 using System;
@@ -13,10 +11,9 @@ namespace Emby.Server.Implementations.Library
 {
     public static class MediaStreamSelector
     {
-        public static int? GetDefaultAudioStreamIndex(List<MediaStream> streams, string[] preferredLanguages, bool preferDefaultTrack)
+        public static int? GetDefaultAudioStreamIndex(IReadOnlyList<MediaStream> streams, IReadOnlyList<string> preferredLanguages, bool preferDefaultTrack)
         {
-            streams = GetSortedStreams(streams, MediaStreamType.Audio, preferredLanguages)
-               .ToList();
+            var sortedStreams = GetSortedStreams(streams, MediaStreamType.Audio, preferredLanguages);
 
             if (preferDefaultTrack)
             {
@@ -28,24 +25,15 @@ namespace Emby.Server.Implementations.Library
                 }
             }
 
-            var stream = streams.FirstOrDefault();
-
-            if (stream != null)
-            {
-                return stream.Index;
-            }
-
-            return null;
+            return sortedStreams.FirstOrDefault()?.Index;
         }
 
         public static int? GetDefaultSubtitleStreamIndex(
             IEnumerable<MediaStream> streams,
-            string[] preferredLanguages,
+            IReadOnlyList<string> preferredLanguages,
             SubtitlePlaybackMode mode,
             string audioTrackLanguage)
         {
-            MediaStream stream = null;
-
             if (mode == SubtitlePlaybackMode.None)
             {
                 return null;
@@ -59,6 +47,7 @@ namespace Emby.Server.Implementations.Library
                 .ThenByDescending(x => x.IsDefault)
                 .ToList();
 
+            MediaStream? stream = null;
             if (mode == SubtitlePlaybackMode.Default)
             {
                 // Prefer embedded metadata over smart logic
@@ -95,26 +84,27 @@ namespace Emby.Server.Implementations.Library
             return stream?.Index;
         }
 
-        private static IEnumerable<MediaStream> GetSortedStreams(IEnumerable<MediaStream> streams, MediaStreamType type, string[] languagePreferences)
+        private static IEnumerable<MediaStream> GetSortedStreams(IEnumerable<MediaStream> streams, MediaStreamType type, IReadOnlyList<string> languagePreferences)
         {
             // Give some preference to external text subs for better performance
-            return streams.Where(i => i.Type == type)
+            return streams
+                .Where(i => i.Type == type)
                 .OrderBy(i =>
-            {
-                var index = FindIndex(languagePreferences, i.Language);
+                {
+                    var index = languagePreferences.FindIndex(x => string.Equals(x, i.Language, StringComparison.OrdinalIgnoreCase));
 
-                return index == -1 ? 100 : index;
-            })
-                 .ThenBy(i => GetBooleanOrderBy(i.IsDefault))
-                 .ThenBy(i => GetBooleanOrderBy(i.SupportsExternalStream))
-                 .ThenBy(i => GetBooleanOrderBy(i.IsTextSubtitleStream))
-                 .ThenBy(i => GetBooleanOrderBy(i.IsExternal))
-                 .ThenBy(i => i.Index);
+                    return index == -1 ? 100 : index;
+                })
+                .ThenBy(i => GetBooleanOrderBy(i.IsDefault))
+                .ThenBy(i => GetBooleanOrderBy(i.SupportsExternalStream))
+                .ThenBy(i => GetBooleanOrderBy(i.IsTextSubtitleStream))
+                .ThenBy(i => GetBooleanOrderBy(i.IsExternal))
+                .ThenBy(i => i.Index);
         }
 
         public static void SetSubtitleStreamScores(
-            List<MediaStream> streams,
-            string[] preferredLanguages,
+            IReadOnlyList<MediaStream> streams,
+            IReadOnlyList<string> preferredLanguages,
             SubtitlePlaybackMode mode,
             string audioTrackLanguage)
         {
@@ -123,15 +113,14 @@ namespace Emby.Server.Implementations.Library
                 return;
             }
 
-            streams = GetSortedStreams(streams, MediaStreamType.Subtitle, preferredLanguages)
-                .ToList();
+            var sortedStreams = GetSortedStreams(streams, MediaStreamType.Subtitle, preferredLanguages);
 
             var filteredStreams = new List<MediaStream>();
 
             if (mode == SubtitlePlaybackMode.Default)
             {
                 // Prefer embedded metadata over smart logic
-                filteredStreams = streams.Where(s => s.IsForced || s.IsDefault)
+                filteredStreams = sortedStreams.Where(s => s.IsForced || s.IsDefault)
                     .ToList();
             }
             else if (mode == SubtitlePlaybackMode.Smart)
@@ -139,54 +128,37 @@ namespace Emby.Server.Implementations.Library
                 // Prefer smart logic over embedded metadata
                 if (!preferredLanguages.Contains(audioTrackLanguage, StringComparison.OrdinalIgnoreCase))
                 {
-                    filteredStreams = streams.Where(s => !s.IsForced && preferredLanguages.Contains(s.Language, StringComparison.OrdinalIgnoreCase))
+                    filteredStreams = sortedStreams.Where(s => !s.IsForced && preferredLanguages.Contains(s.Language, StringComparison.OrdinalIgnoreCase))
                         .ToList();
                 }
             }
             else if (mode == SubtitlePlaybackMode.Always)
             {
                 // always load the most suitable full subtitles
-                filteredStreams = streams.Where(s => !s.IsForced)
-                    .ToList();
+                filteredStreams = sortedStreams.Where(s => !s.IsForced).ToList();
             }
             else if (mode == SubtitlePlaybackMode.OnlyForced)
             {
                 // always load the most suitable full subtitles
-                filteredStreams = streams.Where(s => s.IsForced).ToList();
+                filteredStreams = sortedStreams.Where(s => s.IsForced).ToList();
             }
 
             // load forced subs if we have found no suitable full subtitles
-            if (filteredStreams.Count == 0)
-            {
-                filteredStreams = streams
-                    .Where(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase))
-                    .ToList();
-            }
+            var iterStreams = filteredStreams.Count == 0
+                ? sortedStreams.Where(s => s.IsForced && string.Equals(s.Language, audioTrackLanguage, StringComparison.OrdinalIgnoreCase))
+                : filteredStreams;
 
-            foreach (var stream in filteredStreams)
+            foreach (var stream in iterStreams)
             {
                 stream.Score = GetSubtitleScore(stream, preferredLanguages);
             }
         }
 
-        private static int FindIndex(string[] list, string value)
-        {
-            for (var i = 0; i < list.Length; i++)
-            {
-                if (string.Equals(list[i], value, StringComparison.OrdinalIgnoreCase))
-                {
-                    return i;
-                }
-            }
-
-            return -1;
-        }
-
-        private static int GetSubtitleScore(MediaStream stream, string[] languagePreferences)
+        private static int GetSubtitleScore(MediaStream stream, IReadOnlyList<string> languagePreferences)
         {
             var values = new List<int>();
 
-            var index = FindIndex(languagePreferences, stream.Language);
+            var index = languagePreferences.FindIndex(x => string.Equals(x, stream.Language, StringComparison.OrdinalIgnoreCase));
 
             values.Add(index == -1 ? 0 : 100 - index);
 
diff --git a/Emby.Server.Implementations/LiveTv/LiveTvManager.cs b/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
index 6a9a3077c..5df18f6de 100644
--- a/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
+++ b/Emby.Server.Implementations/LiveTv/LiveTvManager.cs
@@ -312,7 +312,7 @@ namespace Emby.Server.Implementations.LiveTv
             {
                 if (isVideo)
                 {
-                    mediaSource.MediaStreams.AddRange(new List<MediaStream>
+                    mediaSource.MediaStreams = new MediaStream[]
                     {
                         new MediaStream
                         {
@@ -329,11 +329,11 @@ namespace Emby.Server.Implementations.LiveTv
                             // Set the index to -1 because we don't know the exact index of the audio stream within the container
                             Index = -1
                         }
-                    });
+                    };
                 }
                 else
                 {
-                    mediaSource.MediaStreams.AddRange(new List<MediaStream>
+                    mediaSource.MediaStreams = new MediaStream[]
                     {
                         new MediaStream
                         {
@@ -341,7 +341,7 @@ namespace Emby.Server.Implementations.LiveTv
                             // Set the index to -1 because we don't know the exact index of the audio stream within the container
                             Index = -1
                         }
-                    });
+                    };
                 }
             }
 
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
index 532790019..e0eaa8e58 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/HdHomerun/HdHomerunHost.cs
@@ -446,7 +446,7 @@ namespace Emby.Server.Implementations.LiveTv.TunerHosts.HdHomerun
             {
                 Path = url,
                 Protocol = MediaProtocol.Udp,
-                MediaStreams = new List<MediaStream>
+                MediaStreams = new MediaStream[]
                 {
                     new MediaStream
                     {
diff --git a/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs b/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
index dd83f9a53..2a468e14d 100644
--- a/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
+++ b/Emby.Server.Implementations/LiveTv/TunerHosts/M3UTunerHost.cs
@@ -170,7 +170,7 @@ namespace Emby.Server.Implementations.LiveTv.TunerHosts
             {
                 Path = path,
                 Protocol = protocol,
-                MediaStreams = new List<MediaStream>
+                MediaStreams = new MediaStream[]
                 {
                     new MediaStream
                     {
diff --git a/Emby.Server.Implementations/Localization/LocalizationManager.cs b/Emby.Server.Implementations/Localization/LocalizationManager.cs
index dbd70342a..281dbb00b 100644
--- a/Emby.Server.Implementations/Localization/LocalizationManager.cs
+++ b/Emby.Server.Implementations/Localization/LocalizationManager.cs
@@ -147,13 +147,7 @@ namespace Emby.Server.Implementations.Localization
                         threeletterNames = new[] { parts[0], parts[1] };
                     }
 
-                    list.Add(new CultureDto
-                    {
-                        DisplayName = name,
-                        Name = name,
-                        ThreeLetterISOLanguageNames = threeletterNames,
-                        TwoLetterISOLanguageName = twoCharName
-                    });
+                    list.Add(new CultureDto(name, name, twoCharName, threeletterNames));
                 }
             }
 
diff --git a/Jellyfin.Api/Controllers/SearchController.cs b/Jellyfin.Api/Controllers/SearchController.cs
index 26acb4cdc..6fcd2ae40 100644
--- a/Jellyfin.Api/Controllers/SearchController.cs
+++ b/Jellyfin.Api/Controllers/SearchController.cs
@@ -121,11 +121,7 @@ namespace Jellyfin.Api.Controllers
                 IsSports = isSports
             });
 
-            return new SearchHintResult
-            {
-                TotalRecordCount = result.TotalRecordCount,
-                SearchHints = result.Items.Select(GetSearchHintResult).ToArray()
-            };
+            return new SearchHintResult(result.Items.Select(GetSearchHintResult).ToArray(), result.TotalRecordCount);
         }
 
         /// <summary>
diff --git a/MediaBrowser.Controller/LiveTv/LiveTvChannel.cs b/MediaBrowser.Controller/LiveTv/LiveTvChannel.cs
index e63874f21..335222da9 100644
--- a/MediaBrowser.Controller/LiveTv/LiveTvChannel.cs
+++ b/MediaBrowser.Controller/LiveTv/LiveTvChannel.cs
@@ -134,7 +134,7 @@ namespace MediaBrowser.Controller.LiveTv
             {
                 Id = Id.ToString("N", CultureInfo.InvariantCulture),
                 Protocol = PathProtocol ?? MediaProtocol.File,
-                MediaStreams = new List<MediaStream>(),
+                MediaStreams = Array.Empty<MediaStream>(),
                 Name = Name,
                 Path = Path,
                 RunTimeTicks = RunTimeTicks,
diff --git a/MediaBrowser.Controller/Persistence/IItemRepository.cs b/MediaBrowser.Controller/Persistence/IItemRepository.cs
index 837bf0bb2..f7cc7841f 100644
--- a/MediaBrowser.Controller/Persistence/IItemRepository.cs
+++ b/MediaBrowser.Controller/Persistence/IItemRepository.cs
@@ -81,7 +81,7 @@ namespace MediaBrowser.Controller.Persistence
         /// <param name="id">The identifier.</param>
         /// <param name="streams">The streams.</param>
         /// <param name="cancellationToken">The cancellation token.</param>
-        void SaveMediaStreams(Guid id, List<MediaStream> streams, CancellationToken cancellationToken);
+        void SaveMediaStreams(Guid id, IReadOnlyList<MediaStream> streams, CancellationToken cancellationToken);
 
         /// <summary>
         /// Gets the media attachments.
diff --git a/MediaBrowser.Model/Dlna/ContentFeatureBuilder.cs b/MediaBrowser.Model/Dlna/ContentFeatureBuilder.cs
index 58b06ca1d..6e129246b 100644
--- a/MediaBrowser.Model/Dlna/ContentFeatureBuilder.cs
+++ b/MediaBrowser.Model/Dlna/ContentFeatureBuilder.cs
@@ -115,7 +115,7 @@ namespace MediaBrowser.Model.Dlna
             return "DLNA.ORG_PN=" + orgPn + orgOp + orgCi + dlnaflags;
         }
 
-        public static List<string> BuildVideoHeader(
+        public static IEnumerable<string> BuildVideoHeader(
             DeviceProfile profile,
             string container,
             string videoCodec,
diff --git a/MediaBrowser.Model/Dlna/StreamInfo.cs b/MediaBrowser.Model/Dlna/StreamInfo.cs
index cf8465067..a678c54e7 100644
--- a/MediaBrowser.Model/Dlna/StreamInfo.cs
+++ b/MediaBrowser.Model/Dlna/StreamInfo.cs
@@ -675,7 +675,7 @@ namespace MediaBrowser.Model.Dlna
             return string.Format(CultureInfo.InvariantCulture, "{0}/videos/{1}/stream{2}?{3}", baseUrl, ItemId, extension, queryString);
         }
 
-        private static List<NameValuePair> BuildParams(StreamInfo item, string accessToken)
+        private static IEnumerable<NameValuePair> BuildParams(StreamInfo item, string accessToken)
         {
             var list = new List<NameValuePair>();
 
@@ -805,34 +805,12 @@ namespace MediaBrowser.Model.Dlna
             return list;
         }
 
-        public List<SubtitleStreamInfo> GetExternalSubtitles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, string baseUrl, string accessToken)
-        {
-            return GetExternalSubtitles(transcoderSupport, includeSelectedTrackOnly, false, baseUrl, accessToken);
-        }
-
-        public List<SubtitleStreamInfo> GetExternalSubtitles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, bool enableAllProfiles, string baseUrl, string accessToken)
-        {
-            var list = GetSubtitleProfiles(transcoderSupport, includeSelectedTrackOnly, enableAllProfiles, baseUrl, accessToken);
-            var newList = new List<SubtitleStreamInfo>();
-
-            // First add the selected track
-            foreach (SubtitleStreamInfo stream in list)
-            {
-                if (stream.DeliveryMethod == SubtitleDeliveryMethod.External)
-                {
-                    newList.Add(stream);
-                }
-            }
-
-            return newList;
-        }
-
-        public List<SubtitleStreamInfo> GetSubtitleProfiles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, string baseUrl, string accessToken)
+        public IEnumerable<SubtitleStreamInfo> GetSubtitleProfiles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, string baseUrl, string accessToken)
         {
             return GetSubtitleProfiles(transcoderSupport, includeSelectedTrackOnly, false, baseUrl, accessToken);
         }
 
-        public List<SubtitleStreamInfo> GetSubtitleProfiles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, bool enableAllProfiles, string baseUrl, string accessToken)
+        public IEnumerable<SubtitleStreamInfo> GetSubtitleProfiles(ITranscoderSupport transcoderSupport, bool includeSelectedTrackOnly, bool enableAllProfiles, string baseUrl, string accessToken)
         {
             var list = new List<SubtitleStreamInfo>();
 
diff --git a/MediaBrowser.Model/Dto/MediaSourceInfo.cs b/MediaBrowser.Model/Dto/MediaSourceInfo.cs
index ec3b37efa..049e14333 100644
--- a/MediaBrowser.Model/Dto/MediaSourceInfo.cs
+++ b/MediaBrowser.Model/Dto/MediaSourceInfo.cs
@@ -15,7 +15,7 @@ namespace MediaBrowser.Model.Dto
         public MediaSourceInfo()
         {
             Formats = Array.Empty<string>();
-            MediaStreams = new List<MediaStream>();
+            MediaStreams = Array.Empty<MediaStream>();
             MediaAttachments = Array.Empty<MediaAttachment>();
             RequiredHttpHeaders = new Dictionary<string, string>();
             SupportsTranscoding = true;
@@ -88,7 +88,7 @@ namespace MediaBrowser.Model.Dto
 
         public Video3DFormat? Video3DFormat { get; set; }
 
-        public List<MediaStream> MediaStreams { get; set; }
+        public IReadOnlyList<MediaStream> MediaStreams { get; set; }
 
         public IReadOnlyList<MediaAttachment> MediaAttachments { get; set; }
 
diff --git a/MediaBrowser.Model/Dto/MetadataEditorInfo.cs b/MediaBrowser.Model/Dto/MetadataEditorInfo.cs
index e0e889f7d..d098669ba 100644
--- a/MediaBrowser.Model/Dto/MetadataEditorInfo.cs
+++ b/MediaBrowser.Model/Dto/MetadataEditorInfo.cs
@@ -1,7 +1,7 @@
-#nullable disable
 #pragma warning disable CS1591
 
 using System;
+using System.Collections.Generic;
 using MediaBrowser.Model.Entities;
 using MediaBrowser.Model.Globalization;
 using MediaBrowser.Model.Providers;
@@ -19,16 +19,16 @@ namespace MediaBrowser.Model.Dto
             ContentTypeOptions = Array.Empty<NameValuePair>();
         }
 
-        public ParentalRating[] ParentalRatingOptions { get; set; }
+        public IReadOnlyList<ParentalRating> ParentalRatingOptions { get; set; }
 
-        public CountryInfo[] Countries { get; set; }
+        public IReadOnlyList<CountryInfo> Countries { get; set; }
 
-        public CultureDto[] Cultures { get; set; }
+        public IReadOnlyList<CultureDto> Cultures { get; set; }
 
-        public ExternalIdInfo[] ExternalIdInfos { get; set; }
+        public IReadOnlyList<ExternalIdInfo> ExternalIdInfos { get; set; }
 
-        public string ContentType { get; set; }
+        public string? ContentType { get; set; }
 
-        public NameValuePair[] ContentTypeOptions { get; set; }
+        public IReadOnlyList<NameValuePair> ContentTypeOptions { get; set; }
     }
 }
diff --git a/MediaBrowser.Model/Globalization/CultureDto.cs b/MediaBrowser.Model/Globalization/CultureDto.cs
index 5246f87d9..d0cf2aad0 100644
--- a/MediaBrowser.Model/Globalization/CultureDto.cs
+++ b/MediaBrowser.Model/Globalization/CultureDto.cs
@@ -1,7 +1,6 @@
-#nullable disable
 #pragma warning disable CS1591
 
-using System;
+using System.Collections.Generic;
 
 namespace MediaBrowser.Model.Globalization
 {
@@ -10,39 +9,42 @@ namespace MediaBrowser.Model.Globalization
     /// </summary>
     public class CultureDto
     {
-        public CultureDto()
+        public CultureDto(string name, string displayName, string twoLetterISOLanguageName, IReadOnlyList<string> threeLetterISOLanguageNames)
         {
-            ThreeLetterISOLanguageNames = Array.Empty<string>();
+            Name = name;
+            DisplayName = displayName;
+            TwoLetterISOLanguageName = twoLetterISOLanguageName;
+            ThreeLetterISOLanguageNames = threeLetterISOLanguageNames;
         }
 
         /// <summary>
-        /// Gets or sets the name.
+        /// Gets the name.
         /// </summary>
         /// <value>The name.</value>
-        public string Name { get; set; }
+        public string Name { get; }
 
         /// <summary>
-        /// Gets or sets the display name.
+        /// Gets the display name.
         /// </summary>
         /// <value>The display name.</value>
-        public string DisplayName { get; set; }
+        public string DisplayName { get; }
 
         /// <summary>
-        /// Gets or sets the name of the two letter ISO language.
+        /// Gets the name of the two letter ISO language.
         /// </summary>
         /// <value>The name of the two letter ISO language.</value>
-        public string TwoLetterISOLanguageName { get; set; }
+        public string TwoLetterISOLanguageName { get; }
 
         /// <summary>
         /// Gets the name of the three letter ISO language.
         /// </summary>
         /// <value>The name of the three letter ISO language.</value>
-        public string ThreeLetterISOLanguageName
+        public string? ThreeLetterISOLanguageName
         {
             get
             {
                 var vals = ThreeLetterISOLanguageNames;
-                if (vals.Length > 0)
+                if (vals.Count > 0)
                 {
                     return vals[0];
                 }
@@ -51,6 +53,6 @@ namespace MediaBrowser.Model.Globalization
             }
         }
 
-        public string[] ThreeLetterISOLanguageNames { get; set; }
+        public IReadOnlyList<string> ThreeLetterISOLanguageNames { get; }
     }
 }
diff --git a/MediaBrowser.Model/IO/IFileSystem.cs b/MediaBrowser.Model/IO/IFileSystem.cs
index 0f77d6b5b..7207795b0 100644
--- a/MediaBrowser.Model/IO/IFileSystem.cs
+++ b/MediaBrowser.Model/IO/IFileSystem.cs
@@ -199,6 +199,6 @@ namespace MediaBrowser.Model.IO
 
         void SetAttributes(string path, bool isHidden, bool readOnly);
 
-        List<FileSystemMetadata> GetDrives();
+        IEnumerable<FileSystemMetadata> GetDrives();
     }
 }
diff --git a/MediaBrowser.Model/Search/SearchHintResult.cs b/MediaBrowser.Model/Search/SearchHintResult.cs
index 92ba4139e..762a9a078 100644
--- a/MediaBrowser.Model/Search/SearchHintResult.cs
+++ b/MediaBrowser.Model/Search/SearchHintResult.cs
@@ -1,4 +1,5 @@
-#nullable disable
+using System.Collections.Generic;
+
 namespace MediaBrowser.Model.Search
 {
     /// <summary>
@@ -7,15 +8,26 @@ namespace MediaBrowser.Model.Search
     public class SearchHintResult
     {
         /// <summary>
-        /// Gets or sets the search hints.
+        /// Initializes a new instance of the <see cref="SearchHintResult" /> class.
         /// </summary>
-        /// <value>The search hints.</value>
-        public SearchHint[] SearchHints { get; set; }
+        /// <param name="searchHints">The search hints.</param>
+        /// <param name="totalRecordCount">The total record count.</param>
+        public SearchHintResult(IReadOnlyList<SearchHint> searchHints, int totalRecordCount)
+        {
+            SearchHints = searchHints;
+            TotalRecordCount = totalRecordCount;
+        }
 
         /// <summary>
-        /// Gets or sets the total record count.
+        /// Gets the search hints.
+        /// </summary>
+        /// <value>The search hints.</value>
+        public IReadOnlyList<SearchHint> SearchHints { get; }
+
+        /// <summary>
+        /// Gets the total record count.
         /// </summary>
         /// <value>The total record count.</value>
-        public int TotalRecordCount { get; set; }
+        public int TotalRecordCount { get; }
     }
 }
diff --git a/MediaBrowser.Providers/MediaInfo/FFProbeAudioInfo.cs b/MediaBrowser.Providers/MediaInfo/FFProbeAudioInfo.cs
index 9eb79c39d..f22965436 100644
--- a/MediaBrowser.Providers/MediaInfo/FFProbeAudioInfo.cs
+++ b/MediaBrowser.Providers/MediaInfo/FFProbeAudioInfo.cs
@@ -84,8 +84,6 @@ namespace MediaBrowser.Providers.MediaInfo
         /// <param name="cancellationToken">The cancellation token.</param>
         protected void Fetch(Audio audio, Model.MediaInfo.MediaInfo mediaInfo, CancellationToken cancellationToken)
         {
-            var mediaStreams = mediaInfo.MediaStreams;
-
             audio.Container = mediaInfo.Container;
             audio.TotalBitrate = mediaInfo.Bitrate;
 
@@ -97,7 +95,7 @@ namespace MediaBrowser.Providers.MediaInfo
 
             FetchDataFromTags(audio, mediaInfo);
 
-            _itemRepo.SaveMediaStreams(audio.Id, mediaStreams, cancellationToken);
+            _itemRepo.SaveMediaStreams(audio.Id, mediaInfo.MediaStreams, cancellationToken);
         }
 
         /// <summary>
diff --git a/MediaBrowser.Providers/MediaInfo/FFProbeVideoInfo.cs b/MediaBrowser.Providers/MediaInfo/FFProbeVideoInfo.cs
index d67e83ab4..77a849d00 100644
--- a/MediaBrowser.Providers/MediaInfo/FFProbeVideoInfo.cs
+++ b/MediaBrowser.Providers/MediaInfo/FFProbeVideoInfo.cs
@@ -172,7 +172,7 @@ namespace MediaBrowser.Providers.MediaInfo
 
             if (mediaInfo != null)
             {
-                mediaStreams = mediaInfo.MediaStreams;
+                mediaStreams = mediaInfo.MediaStreams.ToList();
                 mediaAttachments = mediaInfo.MediaAttachments;
 
                 video.TotalBitrate = mediaInfo.Bitrate;
@@ -202,7 +202,7 @@ namespace MediaBrowser.Providers.MediaInfo
 
                 video.Container = mediaInfo.Container;
 
-                chapters = mediaInfo.Chapters == null ? Array.Empty<ChapterInfo>() : mediaInfo.Chapters;
+                chapters = mediaInfo.Chapters ?? Array.Empty<ChapterInfo>();
                 if (blurayInfo != null)
                 {
                     FetchBdInfo(video, ref chapters, mediaStreams, blurayInfo);
@@ -246,7 +246,7 @@ namespace MediaBrowser.Providers.MediaInfo
             video.Height = videoStream?.Height ?? 0;
             video.Width = videoStream?.Width ?? 0;
 
-            video.DefaultVideoStreamIndex = videoStream == null ? (int?)null : videoStream.Index;
+            video.DefaultVideoStreamIndex = videoStream?.Index;
 
             video.HasSubtitles = mediaStreams.Any(i => i.Type == MediaStreamType.Subtitle);
 
diff --git a/tests/Jellyfin.Server.Implementations.Tests/Library/MediaStreamSelectorTests.cs b/tests/Jellyfin.Server.Implementations.Tests/Library/MediaStreamSelectorTests.cs
new file mode 100644
index 000000000..d59f2f4e5
--- /dev/null
+++ b/tests/Jellyfin.Server.Implementations.Tests/Library/MediaStreamSelectorTests.cs
@@ -0,0 +1,30 @@
+using System;
+using Emby.Server.Implementations.Library;
+using MediaBrowser.Model.Entities;
+using Xunit;
+
+namespace Jellyfin.Server.Implementations.Tests.Library;
+
+public class MediaStreamSelectorTests
+{
+    [Theory]
+    [InlineData(true)]
+    [InlineData(false)]
+    public void GetDefaultAudioStreamIndex_EmptyStreams_Null(bool preferDefaultTrack)
+    {
+        Assert.Null(MediaStreamSelector.GetDefaultAudioStreamIndex(Array.Empty<MediaStream>(), Array.Empty<string>(), preferDefaultTrack));
+    }
+
+    [Theory]
+    [InlineData(true)]
+    [InlineData(false)]
+    public void GetDefaultAudioStreamIndex_WithoutDefault_NotNull(bool preferDefaultTrack)
+    {
+        var streams = new[]
+        {
+            new MediaStream()
+        };
+
+        Assert.NotNull(MediaStreamSelector.GetDefaultAudioStreamIndex(streams, Array.Empty<string>(), preferDefaultTrack));
+    }
+}