Anyway to Program Master Volume for my Audio Receiver?

Im trying to program the master volume on the DirecTV remote to only use my Audio receiver which is programmed to AV1 instead of the TV volume...

I also would like to know if there is a way when i press the off button that it turns off the DirecTV box, TV and also what its programmed to AV1 which is my audio receiver.

Any info would be greatly appreciated