I keep getting the run-around..

[tinocbr]

Installing my cd player in my 1996 GT, which has a amplifier built-in on both the car and the aftermarket radio, and can't find a harness anywhere. The 1984-present harness from Best Buy doesn't fit the 15-pin socket which i have, they replaced it with a "amplifier bypass". This one comes with 5-6 common wires (ground 12v powerant) and 4 RCA extentions which i just striped and spliced to the coordinating speaker. Problems are now i hear a loud buzzing even when the radio is turned off, along with it being extremely loud (which means its obviously going through two amps).

So i ask this: Why am i getting this buzz? Bad grounds? Also, where is the amp located on my vehicle, what is the way of bypassing the stock amp?

Thank you all in advance.