Music Source Connection Problems

Sounds like a network issue. Normally I’d suggest your iPhone is connecting to a different subnet than your Mac, but it wouldn’t be services that are the problem, but connecting to the speakers. But there is still some sort of network issue, I think, because the Sonos ‘system’ works mainly on the speakers, your controller essentially is just a display to report what the speakers are doing. 

I would recommend that you submit a system diagnostic within 10 minutes of reproducing the issue , from both your devices, and call Sonos Support to discuss it. Don’t post the resulting diagnostic numbers here.

There may be information included in the diagnostic that will help Sonos pinpoint the issue and help you find a solution.

When you speak directly to the Support staff, they have tools at their disposal that will allow them to give you advice specific to your network and Sonos system.

On further rumination, I’m guessing it’s some sort of virus protection / port blocking software, of some type. I have never seen the contents of a diagnostic, but would hope that maybe it would show where the ‘blocking’ command comes from, beyond that it just exists. But the odd thing is that some of the services work, which does suggest something is blocking the Sonos devices from reaching the necessary servers to activate that particular blocked activity.