HDMI-CEC Volume control stopped working after TvOS 16 update

I have my AppleTV 4th gen connected to my Philips TV using HDMI, the TV is connected with HDMI to my Denon amplifier and it receives audio using HDMI-ARC.

The TV has been setup to be controlled by the AppleTV using HDMI-CEC, so I can use the remote control from my iPhone to activate the AppleTV which turns on the TV and the Denon amplifier and I can control the volume of my Denon by using the volume buttons on my iPhone.

I've had this setup for quite a while and it worked like a charm, until iOS16/tvOS16. Currently when I want to change volume using the volume buttons on my iPhone it will change the system volume of my iPhone, not the volume of my Denon.

I did find a workaround; if you change the AppleTV-settings under Control and devices, and disable Control of tv's and receivers and enable it again the volume-control seems to be enabled and I can control the volume of my Denon again. However; after the AppleTV has been in suspend-mode the control doesn't work anymore and I have to apply the same workaround again.

This issue is a bit annoying and seems like a bug to me. If anyone knows of a workaround or setting to persist the volume-control from iPhone I'd really like to know how .

Thanks!