I have an Arc in my “TV room” and a pair of One’s (R + L) in my “Kitchen”.  In the Sonos app, these are in rooms with these names.  With Alexa, I was able to speak to any speaker in either room.  However, I’m trying to switch to Google Assistant and appear to be able to only speak to one speaker (currently the right one in the kitchen).

When I try to add GA to the Arc via the Sonos app, it recognises the Arc but when I click “Open Google Assistant App”, it says “There was a problem adding Google Assistant”.  I’ve got the latest Sonos, Google Home and Google Assistant Apps.  I’ve tried linking and unlinking in Sonos and Google Home.  In Google home, I can see the Sonos speakers in their respective rooms.  I can ask GA on the kitchen speaker to play music in the TV room and it works.  I just can’t add GA to the Arc so I have to shout to the speaker in the kitchen.

Is this normal (i.e. a limitation) or am I missing something ?  I don’t want to add a separate Google device as I would expect to be able to use my Sonos speakers.