I just installed a JVC Arsenal KD-A645 Arsenal CD receiver and as I turn up the volume on it, the speakers begin to crackle and disort the music playing. I messed around with the Bass, Treble, and Middle and could not find that right setting to stop the speakers from acting up. The speakers are aftermarket kickers, probably about four years old. I never had a problem with them while using the stock headunit and was able to play music much louder. I know the new headunit does have a larger amp compared to the old one. Can someone please give me some tips on what levels of bass, treble and middle to use and also what Hz would work the best? I drive a 06 cobalt LT.