Nissan Repair: Radio, side fender, ground wires

Question
About 2 months ago I was hit in a parking lot; it smashed in the front passenger side fender. Ever since then my radio has this buzzing sound to it, and it only happens when the car is on. If I just use the battery there is no noise. I’ve had it in the dealership once and they say they don’t hear anything, but I really noticed it today when I was installing my new XM radio. I really would like to fix this problem its annoying.

Thanks,
William P. Ruiter  

Answer
well, i cannot say for certain what is wrong w/o knowing what car this is, but im going to take a stab at this.  is the "buzzing" relevant to the rpms?  does the "note" of the "buzz" increase and decrease with the acceleration?  im guessing that when you were hit on the passenger side (possibly battery side) there were some negative ground wires that were also damaged with the impact creating a semi open circuit in the system.  i would check any ground wires running along the side of the damaged car and re route them to another safe grounding point.  also, if your system has an amp you will have a positive and negative wires to the battery and grounding point, this may also be the problem.  if you do have an amp, unhook it and see if the noise goes away.  only other suggestion i can say for now is to check out a junkyard and see if you could borrow a factory deck and swap that out to see if that fixes your problem.  electrical is a pain, its trial and error.  i hope this helps, ive never heard of this before!  good luck bill.  let me know how this turns out. xxp_sebby@yahoo.com