Sup folks,

 

I just installed a Avic-D3 in my wife's 2005 Nissan Maxima, and the front and rear door speakers are wired directly to the head

unit (Those work perfectly fine no issues), however I installed new 6x9's in the rear deck lid which required an amp, and I'm getting this weird interference noise. When I unplug the rca's at the amp the noise stops which leads me to believe that the unit is possibly trying to ground through the sheilds of the rca's????? What I noticed during the install was; the ground lead on the aftermarket plug-in wiring harness did not work, so I grounded the wire to the metal plate behind the dash, and the unit came on. I spoke briefly with some guy, and he told me he knew what it was, and could remedy the problem for $20.00 I asked him if a ground loop isolator would fix the problem, and he said no, and insisted that I remove the radio before driving 6 miles to him to fix.

 

He did not want to share what he knew, and insisted that the problem was behind the head unit.

Does anyone have a clue as to what I can do myself without having to pay this guy?