i have a 720 watt jenson amplifier with 2 12' sony explods. when i turn my car and play a song that has some bass and let it play for a while then change the song the next song will play but the bass like sticks on from the first song i played and when i unplug my white RCA cable it works fine but is only getting half the power to it. the amp works fine in other vehicles. please help.