Hi @Cambridgehank, 

Thanks for reaching out to the Sonos community and for letting us know about your concern. Let me share this with you. Updating your system means you're getting the latest security patches and program bug fixes to some applications. There may be advantages and disadvantages when you upgrade like compatibility issues with other software. We respect your decision if you want to wait for at least two software revisions to Big Sur. Apple knows their product more than us. Big Sur is a Mac new software and we don't have any information to share about it. We can wait for suggestions and feedback from our Sonos community members, who have updated their MacOS, they might provide their inputs about this.

Please let me know if you have any further questions or concerns, we’ll be glad to assist you. 

Thank you.  That is what I thought I was doing, looking for feedback from other users.

My upgrade to Big Sur (MacBook Pro and an iMac)

I upgraded the OS to Big Sur on the MacBook first and I installed the latest Sonos S2 Controller.  

NON FUNCTIONAL QUEUE ISSUE: When I added a song or an album or a  playlist to the controller’s queue on the MacBook, the queue (the lower section of the middle pane of the controller) showed zero songs, lost its functionality and displayed “unable to browse music” message.  I should note that songs I added to the queue played OK on the speakers except that I could not control music with the queue.

The Sonos controller on the iMac (No Big Sur update yet but with updated SONOS S2 controller) did not have the same issue and was working just fine.

Comparing “System Preferences”  in Big Sur OS on the MacBook and the previous OS on the iMac I noticed a difference in “Security  and Privacy”  and the two “Firewall” and “Privacy” tabs. In Big Sur, Apple moved SONOS stuff from one tab to the other.

I then updated the OS on the iMac to Big Sur.  Lo and behold, the OS update to Big Sur on the iMac fixed the Controller’s Queue issue on the MacBook.  SONOS cannot function properly with different OS / firewall and privacy settings on the same SONOS system.  It makes sense.

My advice would be not to - having a nightmare with Big Sur in relation to all sorts of stuff including Sonos!