I have a Google Assistant related issue--my Sonos System (Arc, Sub+Move) is linked to Google Assistant and everything worked perfectly fine so far. A few days ago I had to restart all devices as they were not found in the Sonos App. Google Assistant is still linked to my Sonos Move but does not work any longer (Assistant is not available).
The Arc has no Google Assistant linked any longer and is also not found when I try to locate it both over the Google Home and Sonos App.
Thanks for your help!
As I did not change anything and it stopped working I guess this is related to the latest Software Update?!
Btw I have also sent a diagnostic report with ID 257824096. Maybe you can see what went wrong.
Best answer by Seikatsu
Just went through this mess as well, so thought I'd share the solution:
My sequence was:
1) existing S1 setup - no Google Assistant capable device
2) added Move to S1 setup, configured the Assistant fine
3) added Arc to the system, which triggered the entire migration to S2 (rendering about 4 legacy speakers useless)
4) had to reset Move to re-add to S2 setup with Arc
5) Move played music, but Assistant feature stopped
6) Google Home app couldn't find neither Arc nor Move to set up Assistant
Finally realized that while the S1 network wasn't Assistant capable, someone had added one of the now defunct Play5 speakers as an audio device. Since that speaker wasn't plugged in, it didn't show up even on any migration related lists.
Unlinking Sonos from Google Home completely, and triggering a new re-linking via S2 app finally found Arc & Move.
Bottom line: if you have done S1-S2 migration too, get rid of the legacy connection between Google & Sonos, it will block the new devices finding.