Sadly this doesn't work for me, I get the same error. When run
automatically it says it can't do it, and when run manually it just
changes my phone media volume.It seems that this is actually a
deliberate change because Google won't pay Sonos royalti...
I'm having an identical issue (although I use different volumes due to
wanting different levels throughout the home), it started at the same
time as yours but I've only just investigated. I'm not sure if this is
relevant, but while I get the same err...