One room setup, but u need to make the default Video and Audio Video endpoint for the most used case AVR or TV, in my case I have the TV as default, created a custom menu for the AVR, Power On/Off, Vol +, Vol -, Mute
This is the exact setup in my living room, if I need an amplified sound I just turn AVR custom key On and via programing it brings TV sound to zero and adjust sound, I then use the other 2 custom buttons Vol+/Vol- to change Volume
I find the 2 room setup a bit stupid and it’s one of the issues with C4 that currently not addressed properly!