iPhone Problem

Maybe somebody here will have an idea about this…

I have an iPhone. I use it in my car via a Motorola HF850 Bluetooth "hands free" connection for two things…as a phone and to play music via its iPod functions. The phone part has always worked fine and still does. But a few days ago, the music/iPod part ceased to function the same way. I can make phone calls and hear the audio through my car's speaker system. But when I play music, the music no longer comes through the car's speakers. Both functions work fine on the iPhone when it is not connected to the car.

It feels like I'm trapped in one of those technology jurisdictional disputes. If I call the guy who installed all this for me in my car, he's going to tell me the Bluetooth is working fine with the phone so the problem must be in my iPhone. But I just know that if I take the iPhone into the Apple Store, they're going to tell me the problem must be with my car installation…and anyway, I can't replicate the problem in the Apple Store. It only occurs in my car.

An Internet source yields no info on why, though the phone plays its audio through my car speakers, the music part of the same device will not. Last week, my iPhone upgraded itself to the new 4.0 software but the problem did not pop up until a few days later. It all worked fine for a time after the upgrade so it doesn't seem to be related to that.

Anyone?