1. MacBook has been able to connect/control Sonos devices on this home network before (this inability to connect is recent).
2. I also have Sonos app on other devices (an iPhone, an iPad, and a Mac Mini), and Sonos works fine from all these other devices. I'm able to connect and control Sonos without any problems. The issue is only on the MacBook, as far as I can tell.
3. When the Sonos app on the MacBook prompted me to connect by simultaneously pressing the play and plus buttons on any Sonos device-- I tried that, and it had no effect (still unable to connect).
4. I've double checked the MacBook's network settings and verified the following:
--- MacBook *is* on my WiFi network and *does* have internet connectivity. I'm able to use other services on my home network from the MacBook (such as printing, remote desktop control of Mac Mini, etc.).
--- MacBook firewall settings have not changed-- it's not in "stealth" mode, and Sonos app connections are allowed.
I'm baffled, and would appreciate any hints or suggestions for diagnosing this problem!
Best answer by ChrisATXView original