I am wondering if anyone can tell me where the speaker relay is??? On a 1998 Cadillac El Dorado. When I start the car, the stereo plays. Then after driving down the road a ways, only the left side plays. Even without hitting bumps. Then after a few minutes the whole sound quits. Seems to be worse when it is hot outside for some reason. And seems to work longer in winter before sound goes off if at all. Has original Bose system. Also needing to find chrome hubcaps with Cadillac emblems in center. One broke and the tire shop broke one.