OMG, that's EXACTLY what's happening to me! I have been trying for 3 months to figure this problem out. My husband took the car in, they said talk to apple, took the iphone in, they said talk to Chevy! Talk about the runaround. My kids have iphones, so we have narrowed the problem down. My oldest has the old software, 3.1, works fine in my brand new 2011 Tahoe, the youngest has the new software, just like me, stops playing halfway through the song. My iphone worked prior to the upgrade, now I can't "downgrade". I've owned 3 iphones, now my kids have them and Apple won't stand behind it's product! So now, guess what, I'm thinking of changing to a different phone and I won't hesitate to tell friends, family or anyone else, just what I think of it. Prior to this situation, I was pro iphone, but now, after spending hundreds of $ on itunes, phones, etc., it just makes me sick!
I upgraded my iPhone4 to iOS4.1. Now when I try to play the iPod function through the audio system of my Chevy Malibu, it plays for @50 secs and stops. Worked great before that. I tried my old iP3 and it works great, so I've been using it for music. That's not a good solution, just another thing to carry.
Can't downgrade and Apple, GM/Chevy are all telling me to talk to the other guy. Any suggestions for how to wrestle this thing to the ground? No one has an answer. Software? Firmware? This seems to be an intractable problem with lots of gray area and no one taking responsibility!

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