So just to clarify ​@MoPac is this a user-created playlist held within the Amazon music service? If so, are you using their ‘prime’ or ‘ultimate’ music service and have you ever swapped between prime and ultimate services (or vice versa) since the playlist was created.

What happens if you create a new playlist - does that cause the same issue?

 It is Amazon Ultimate.  I’ll try a new playlist, but the size of the playlist may influence whether the error shows or not.  All my playlists are smaller than 500 tracks because of the Amazon track limit of 500. So building a new one may take some time.

 Just did a smaller playlist and the error did not show.  The larger playlists cause this error which tells me Sonos is not giving enough time for the playlist to load.  In the end it does load.

Yes, I tried it earlier too with a 100 track playlist and that worked for me on an iPad controller (attached). I’m also using Amazon Ultimate.

 Sonos just needs to give more time for the playlist to load before generating the error.  I know I could just ignore the error and watch for the load to finish, but the error showing is sloppy programming.  How many folks just back out when they see that error before allowing enough time for the operation to finish.

Can’t say I’ve come across the issue ​@MoPac, but then again my own Amazon playlists are 100 tracks or less, as that appears to be the limit when loading an Amazon user-created playlist to a Sonos queue using the play/shuffle buttons.

 Yes.  That’s why I use Play Now or Add to End of Queue.  Gives me at least 500.