Disable HDMI sec

Hi,

I did find an older post about disabling HDMI cec, since Volumio isn’t displaying anything useful anyway I’d like to disable this. I’ve actually started to prioritize my Chromecast in order to play music via spotify… What is the most current method to do this?

For now I’d like to keep the Pi connected, since sometimes I use a second card to boot openelec and play a movie.

Setup:
Chromecast -> HDMI -> LG TV -> Optical -> Receiver
Volumio -> HDMI -> LG TV + COAX -> Receiver

Thanks