2006 audi a4 2.0t

hey guys im havin a problem on my own ladys' car and it sucks cause she won't let me hear the end of it.  we put a Pioneer D1 in and had to relocate the factory head so that a bunch of false codes don't acure. we put a 5 channel arc amp to the stock speakers and one 12 sub. the problem is that when we turn on the headlights (hid) we hear the feed back noise through the spkrs and it does not change to the acceleration of the engine, what are some possible solutions to fixing this to help her stop nagging me!!! thanks

found out the problem on the headlights. we needed to wire the rca's down the center council and under the driver seat and them back. having them under the driver side dash was to close the facrtory electronics and creating the feedback. so not e to all.