Hi, we've been noticing this issue for the past few weeks: when a TV is turned on, unrelated rooms that are also not grouped with the TV may begin playing music.
Here is a Diagnostic captured a minute or two after the issue occured: 605248757
We have 3 tvs in the house, each has either a Beam or an Arc.
To reproduce this occasional problem:
1. Make sure all Sonos products are not playing any audio.
2. Turn on a TV that is connected to either a Beam or an Arc.
3. Observe the connected product will properly begin playing TV audio, but other products will begin playing music.
Let me know if you need any more info, thanks!
Best answer by Ken_Griffiths
You may ‘perhaps’ find it quicker to speak with Sonos Support via this LINK, as this is mainly a Sonos user-community and even though Staff do pickup on some posts here, there is no guarantee that might happen, particularly during weekends.
However, have you considered rebooting your router/local-network and/or power-cycling your Sonos devices to see if that resolves the issue? - it may just save you some time by giving that a try first.