My head unit runs through an amp and then out to four speaker in the boat. Last time we were out all of a sudden (I wasn't in the boat when it happened so I don't know if there were any other symptoms) we lost all the bass at all four speakers. So right now sound comes out of all four speakers but it's so tinny it's painful to listen to. I've messed with the settings on the stereo and the amp, and it doesn't do anything. Any thoughts? Is this how amps die?