2 files changed, 5 insertions, 4 deletions
diff --git a/MediaBrowser.Providers/Music/AlbumMetadataService.cs b/MediaBrowser.Providers/Music/AlbumMetadataService.cs
index a39bd16ce..25698d8cb 100644
--- a/MediaBrowser.Providers/Music/AlbumMetadataService.cs
+++ b/MediaBrowser.Providers/Music/AlbumMetadataService.cs
@@ -47,11 +47,11 @@ namespace MediaBrowser.Providers.Music
         protected override bool EnableUpdatingStudiosFromChildren => true;
 
         /// <inheritdoc />
-        protected override IList<BaseItem> GetChildrenForMetadataUpdates(MusicAlbum item)
+        protected override IReadOnlyList<BaseItem> GetChildrenForMetadataUpdates(MusicAlbum item)
             => item.GetRecursiveChildren(i => i is Audio);
 
         /// <inheritdoc />
-        protected override ItemUpdateType UpdateMetadataFromChildren(MusicAlbum item, IList<BaseItem> children, bool isFullRefresh, ItemUpdateType currentUpdateType)
+        protected override ItemUpdateType UpdateMetadataFromChildren(MusicAlbum item, IReadOnlyList<BaseItem> children, bool isFullRefresh, ItemUpdateType currentUpdateType)
         {
             var updateType = base.UpdateMetadataFromChildren(item, children, isFullRefresh, currentUpdateType);
 
diff --git a/MediaBrowser.Providers/Music/ArtistMetadataService.cs b/MediaBrowser.Providers/Music/ArtistMetadataService.cs
index 1f342c0db..8af6de925 100644
--- a/MediaBrowser.Providers/Music/ArtistMetadataService.cs
+++ b/MediaBrowser.Providers/Music/ArtistMetadataService.cs
@@ -1,6 +1,7 @@
 #pragma warning disable CS1591
 
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using MediaBrowser.Controller.Configuration;
 using MediaBrowser.Controller.Entities;
 using MediaBrowser.Controller.Entities.Audio;
@@ -28,7 +29,7 @@ namespace MediaBrowser.Providers.Music
         protected override bool EnableUpdatingGenresFromChildren => true;
 
         /// <inheritdoc />
-        protected override IList<BaseItem> GetChildrenForMetadataUpdates(MusicArtist item)
+        protected override IReadOnlyList<BaseItem> GetChildrenForMetadataUpdates(MusicArtist item)
         {
             return item.IsAccessedByName
                 ? item.GetTaggedItems(new InternalItemsQuery
@@ -36,7 +37,7 @@ namespace MediaBrowser.Providers.Music
                     Recursive = true,
                     IsFolder = false
                 })
-                : item.GetRecursiveChildren(i => i is IHasArtist && !i.IsFolder);
+                : item.GetRecursiveChildren(i => i is IHasArtist && !i.IsFolder).ToImmutableArray();
         }
     }
 }