did anyone on here add a subwoofer to their GS... mainly for ppl with navi... when i turn the power off for the audio the sub goes nuts and just hits hard as hell... and it does it when i start up the car and turn it off

 

Thats your amp.

 

assuming you have an aftermarket amp and sub setup, the amp and the headunit is being powered on at the same time. that causes the pop sound. you need a simple delay circuit to delay the turn on of the amp.

 

i have a full system but i don't have any of these sounds?