i just replaced my old Kenwood KDC-3011 with a Pioneer DEH-P3500. I did not have any engine noise with the Kenwood and now after installing the Pioneer engine noise is a prominent part of listening to the radio and CD player now. Being the radio is the only thing that was replaced and no spearkers were replaced in the process, would the radio alone cause this engine noise to appear or is there something that i am missing? Any suggestions????