That’s odd. I don’t think I’ve ever seen this before. Do those rooms respond to the volume control, even when ‘greyed’ out? I am assuming you’ve already hit ‘Apply’ at the bottom… oh, and checked for firmware updates on all speakers?
I’d likely try two things. First, I’d delete the controller from whatever device you have it installed on, and download a fresh copy. Honestly, I’d be tempted to do a hard reboot of that device between the deletion and redownload process.
When you reinstall, be sure to ‘connect to existing system’, setting up a new system is not the way you want to go.
But, if that doesn’t work, I would submit a system diagnostic within 10 minutes of experiencing this problem, and call Sonos Support to discuss it. But don’t post the resulting diagnostic number here, they get sensitive about GDPR.
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.
Have exact issue "speaker volume is grayed out." Please tell me the solution.
In my case, the speakers had been switched off (or paused) by using the buttons on the speaker. The app was still showing the theoretical volume that would happen if speaker was “unpaused.”