My voltage basically never moves. Nope not on shut down just start up and it's only when I have the ignition on but not fired up, when I fire it up and the radio is already playing, thats when it pops... LOUD!

 

what kind of radio? just out of curiosity turn the volume all the way down and try it again.

 

Still does it, and it has a constant hum/light faint popping while playing. ONly way to stop is by turning it off. I know it's a ground or some type of interference, just haven't looked into it a whole lot. Figured if you already know what it was, it would save me some time and cut knuckles.

 

You have the Mach 460 and you just installed an aftermarket head unit..if so then the amplifiers with the mach 460 don't go so well with all aftermarket cd players. If it was working in the past with this cd player your using, I believe theres a connector for the amps at the drivers door pillar trim.make sure the connector isn't crushed or corroded...ne-waz good luck