Ah, alright I see what you're getting at. I do have two buttons nears the steering wheel, and I ve never seen them in a GP before, and I have no idea what they're used for to be honest. It may or may not having anything to do with the audio.
To be honest, I am probably going to have one of my friends look at it, since they know what they're doing, and I'd rather not mess with ANYTHING that deals with electronics with this car lol