My modest system is a Virgin 360 box HDMI into my JVC 50” tv with an ethernet-wired Beam Gen 2 (with ONE SL surrounds) connected via eARC.

The issue I had was that the volume display kept popping up on the TV every 20 or 30 seconds.

Really annoying.

I noticed that this issue stopped if the sat box was not connected or if I connected the Beam via Optical so clearly the sat box was constantly handshaking with the Beam via CEC. I tried turning off the CEC control on the Virgin box (“helpfully” called One Button) but it made no difference.

So, on the suggestion from another post on here, I bought a HDMI CEC remover adapter for £8 on Amazon, inserted it between the Virgin box and the TV, and the issue was resolved.

This was after several support calls to Sonos and no progress.  I understand that it wasn’t strictly speaking a Sonos issue so their support didn’t extend but it’s clearly a “fix” that will be of use to many of their customer base and ought to be a suggestion on their diagnostics script.

Anyway, I hope someone finds this useful.