Hi all,
My scenario; I use a Sonos AMP for my home cinema setup, and I use an external power amplifier for my subwoofers (not Sonos ones) using the RCA line out from the Sonos AMP.
But I dont want the power amplifier to be powered ON at all times as it consumes electricity and life span of its electronics. So I use a zwave socket wall plug controlled by my HA/rpi4 to switch it on when I listen to music or watching tv. (and off afterwards)
What I’m looking for basically is a state I can use from the Sonos AMP when it plays any sound at all, no matter if its Sonos Radio, Spotify or using my TV’s HDMI ARC for sound.
I can then put in a simple timer to switch off the power amplifier say 5 minutes after the latest sound was made.
Does anyone have any info what state i should look for from the Sonos AMP for my automation? 
And OFC any other ideas if the same automation can be achived in any other way is welcomed
Thanks