Stupid, stupid mistake?

[Black Box]

My system has developed obnoxious RFI (?) interference thru the stereo system. I was putting the sub box back in the car, and was hooking up the amp for the subs and accidentally touched the power wire to the ground connection on the amp. But the wierd thing is, even when I disconnect the amp for the subs (there is another 100W amp that powers the 6x9's in the rear deck), the sound is still there. Obviously, it only makes the noise when the car is running (duh). If the car isn't running, it sounds great, as good as it always has.

Here's what I have:
Kenwood KDC-217 CD receiver
Infinity 3052CF 3.5's in the dash (running right off the receiver)
Kenwood KFC-1368S 5.25's in the doors
Kenwood KFC-6908 6x9's in the deck, running off an MTX Thunder 4122 amp
Infinity Reference 10" 1020W subs running off an MTX Thunder 8302 amp

What did I fry?

TIA
Steve

 

[zam70]

Ah yes...
My guess is you've probably burnt the signal ground foils in the deck.

Easy and realatively cheap fix. Take it to a repair shop or if you are a little handy you could fix it your self.

 

[Black Box]

Thanks zam70

I am not very well versed at car audio, so I'll bring it to a shop.

Steve

 

[GNandTTA]

Before you do that, do a continuity test on the RCA plug ground. Should have 100% continuity. If you don't, take a piece of wire and ground the RCA shield to the case on the deck. See if the noise goes away. You may have lost your only reference to ground and now the RCA shield is acting like an antenna amplifiying any noise that may be presesnt into the center conductor on the RCA plug.