Update PlayToController.cs

Emby.Dlna/PlayTo/PlayToController.cs

@@ -886,7 +886,10 @@ namespace Emby.Dlna.PlayTo
                     return null;
                 }
 
-                mediaSource = await _mediaSourceManager.GetMediaSource(Item, MediaSourceId, LiveStreamId, false, cancellationToken).ConfigureAwait(false);
+                if (_mediaSourceManager != null)
+                {
+                    mediaSource = await _mediaSourceManager.GetMediaSource(Item, MediaSourceId, LiveStreamId, false, cancellationToken).ConfigureAwait(false);
+                }
 
                 return mediaSource;
             }