Not much info to go on here. I’d probably recommend downloading a fresh copy from the Sonos website. 

Thx. I’ll give that a try

If that won’t help, please check the following setting within MacOS:

System Preferences > Privacy & Security > Local Network > toggle 'osquery' on

Thanks for the response Schlumpf, however I could not find the 'osquery' flag. I Did find the Local Network settings and <Sonos> was “allowed to find and communicate with devices on your local network.” This had been set automatically.

PS I came here after failing to resolve the problem via the phone support after a two hour conversation! They certainly tried hard!

OK… well I’ve just had spontaneous remission of symptoms. I wish I could report a specific change but I cannot identify any specific (related) change which fixed it but I cannot, sorry.

So I did some more digging and the setting seems to be this:

Privacy and Security> Local Network “Allow the applications below to find and communicate with devices on your local network.”

I toggled the Sonos setting (it was on; I turned it off and on again).

Thanks to comments elsewhere in the community for suggesting this!!!

One thing I’ve learned with electronics of all types, it is never a bad thing to try a reset ;)

Glad you were able to resolve it!