i have a sony high out put head unit in a civic which i don't really think too highly of civic's and lot of performance in any corner, although i do like their engineering. but anyways when ever i hit a beat even with the bass not even turned on and with the system off, the lights on the head unit dim. i mean if other lights on the car dim they don't dim enough for someone to tell. but couple times when i hit a beat it would draw enough power to shut the head unit off. i mean its not even loud to my ears. not to mention the volume is only turned up to about 6 to 7 bars, not even half way may be about (1/3).

what could the problem be? any ideas or advice?