Have bought me a new system! Radio Avh-P6600DVD front system Hifonics and in the Koffreraum Hifonics ZX12 Dual power amplifiers Crunch and Alpine! have now connected everything to the rehearsal! now I have in the Fronsysten at all no kang anymore and a hum when I turn out the loud strength and give a whistle at the gas. and back I mean the trunk rides it *ggg*, but in the interior almost nothing to hear from the Woofer!! Help!! Gruss jens P.S. Drive a Bmw E36 Coupe