Under the incredibly bad Youtube Content Service - I used to have a saved Artist “Die drei ???? Kids” which contained short stories for my kids.
After upgrading to the new Sonos App, the artist still comes up and all the “albums” but when I click on an album to listen to, it just shows the message "SOMETHING WENT WRONG". This is for ~90% of the listings.
At the Youtube Music > Artist > list stage, I see all the “albums” but only the ones with a secondary artist listed rin addition to Die drei ???? Kids], will play.