Just got my car back from the body shop for body repairs. I have the 2006 stock shaker 500 w/8 speaker system. When I have the bass to maximum and I play music with heavy bass, I hear a vibration noise. It appears to come from the passenger side rear. I can't seem to pinpoint the noise any further, but it may be coming from the speaker itself. They did have to remove my rear window during the bodywork. I hope it doesn't have to do with that. Any suggestions or ideas before I have to complain to the shop?