Hi @A2BH
Welcome to the Sonos Community!
We are aware of this issue and are currently investigating. Unfortunately, we know of no workaround. Reports of this issue pre-date the latest Sonos software update.
I did see a report from a user that they were able to play by removing the link to the channel in their favourites (My Sonos) and recreating it, though this will presumably not work for any channels you are unable to play from within the Browse menu.
I hope this helps.
"Common sense is the collection of prejudices acquired by age eighteen." - Albert Einstein