EVERY time I get out of my car I get a large shock when I touch the door to close it. I know, "big deal", but it really is annoying... to the point that I try to find other ways to shut the damn door. Is this common for a trep? Should I just buy one of those grounding strip things? What I'm really wondering is if it could be caused by some electrical problem in the car, say with my stereo wireing?