bradfordpoole 10+ year member
Senior VIP Member
I have an AVIC D3 and I had engine noises coming through my speakers so I went to a local audio store and they said the ground loop isolators in the unit were bad and to go to radioshack and buy some. BTW I have Bose so I have the GMOS wiring harness to retain factory door chimes so my door speakers are powered by RCA's on the aftermarket harness to the Front and Rear outputs on the unit. He redid all the grounds and eliminated some of then noise and I went and bought the GPI's and went there plugged up the engine noises go away but theres an echo and my mids are really muffled and my bass is really loud?