@gruvjet I think it would be fun to try to make something like this. There are plenty of stepper motors available that interface with arduino or pi boards, and there are plenty of remotes that interface with those same boards. A mechanical solution would avoid any chance of signal degradation / alteration from any electronic attenuator.
The only challenging issue would be to get some way to clamp the steppers non-destructively to the two volume knobs in a secure way that wasn't ugly as all sin... a 3D printed solution might work (after some prototyping).
Good luck in your quest!
