I have an Avic-D3 with a GEX-P920XM unit installed in a 2004 GMC Sierra 2500HD LT came with bose but without onstar. the factory bose amp and sub are gone as well as all the speakers. 2 days ago I replaced the battery in my truck, and since then I have had a problem with the sound from the xm and the aux input on the front (which i plug into the headphone jack on my iphone). Normal AM/FM/CDs all sound fine, but when I switch to xm or av2 the only sound I get is all bass from the subs, if i turn sub off it get no sound at all. I have reset the GEX-P920XM unit via the pinhole reset button, ch
