hi , i put the aftermaker stereo with gps , work perfect , i put then the speaker piooner frond and rear , work perfect , but now i put a amplifier infinity , i put the amplifier on the top of rear passanger set , the alone set rear , so i run the power (4 gauge) fuse block 4 to 8 to ampifier and remote wire for left side , and wire speaker , RCA 4 channels , coaxial of reverse camera for rigth side , but when i down all volume or put reverse , the stereo no sound and move the wheel for park or somethink i ear a little noise , uuuuuuussssssssss ussssssssss , i run the cable speaker and RCA , for down of wheel , i think maybe the RCA cable have interference , today i test the RCA outside , directly ampl to stereo , and have the same noise , if i disconect the RCA of ampli , any noise , is clear , i dont know what more to do , anyone know any solution ? sorry with my english .. thanks mikee