for some reason my speaker amp cuts out when i raise the volume. some long periods of time it'll work. then the next time i drive, the speakers will cut off when the volume is above 20 or so. i know i am not overpowering my speakers because the amp is an old Kicker Impulse model probably from the 90's and the wattage is enough for my pioneers. i'm thinking it could be the wiring somehow, what can be the problem?