This is solution that worked for me, after two days spent resetting
speakers, routers and accounts - I had 186 ghost speakers and groups
dating back to 2020, deleted them all in the old app version and
suddenly all the group and stereo pair problems ...
This gave me the clue to a solution, without deleting your account.
Instead go to your group in settings and delete the problem group, then
create a new one and give it a new name, one you've not used before.
This enables the new group name to be use...
It was supposed to be family groups being turned off, but I think this
is what broke everything else:
https://support.google.com/assistant/answer/13971691
Still nothing? I keep checking in here, sending feedback on the speaker
but nothing improves - if anything it's getting worse. Asking to play
media on one speaker works fine, asking it to play on a group not at
all. Asking to move the music to a grou...