DaveinIowa

I've lost all sounds from my 2007 Suburban LTZ with the Bose audio/nav system - here's the history:
I had this same issue when I bought the truck with 3000 miles on it, plus the rear DVD would not display (although there was sound to the rear headphones). Warranty repaired it by replacing the wiring harness (the work order said it was pinched in the headliner). At about 18k miles I installed the GMX-320 unlock module and a Motorola bluetooth handsfree module (connected to the GMX-320 harness). All worked great. BTW the GMX-320 is GREAT! Last week at around 25k miles (four months after the module installs) I started to get a high pitched whine people could hear on the other end when using the Motorola handsfree cell phone unit. I couldn't hear it on my end. Then a few days ago I began to hear it when the radio was low, coming through the speakers- sometimes resonably loud. It was tied to engine RPMs (whine would increase with RPMs). Then occasionally the system would go completely silent for a bit. Sometimes the requisite "thump" to the console near the radio would cure it, sometimes turning the radio off then on would cure it. othertimes it just stayed silent. Now all sounds (including things like the electronically generated turn signal "click") are gone.

I'm assuming it's a connection (has been VERY cold here lately). But I wondered if the RPM whine indicates anything to anyone? Any ideas the best places to start checking conennections at? I was guessing starting at the amp since all sounds are gone. Is the amp in the center console?

The truck is still under warranty, but I'm afraid I'd have to remove all the GMX-320 and Handsfree stuff to ensure that I didn't "void" the warranty coverage on the audio/nav system. I'd rather not do that if i can find the bad connection.

Thanks for the help. This forum is amazing (particularly zx1100f1)

Dave