I just got done installing an aftermarket radio and I now noticed my right rear speaker is not working at all, it came back on again and went out again, I pulled the head unit I put in back out and made sure the wiring there was good, when I pulled the rear door panel off I did not see any obvious problems but I did notice it was a little wet in there, I forgot to test the resistance across the speaker to see if it was blown but has anyone had problems with this? There a common spot in the door that the wires corrode away at??