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...
The reason it doesn't work anymore is that Google turned off broadcast
to group, you can only broadcast to a single speaker now. My theory is
that this change also broke media on a group, as I also now cannot play
anything on a group - you can play i...
