I seem to remember to stumble upon a place in the car nav to adjust how sensitive the car stereo sound adjustments are.
In my car the sound from the stereo increases when speed increase, but its really anoying, especially after I did sound deadning since the car is so quiet this is very noticable and I would like to disable it completely.

 

To answer my own question, its called AVC and is in the settings menu on the navi

 

thanks, i'll disable that tomorrow too