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I've done it in Mazda products. Couldnt make it work in Subarus.

And last week in the new Audi A8, in case you've got $90 grand burning a hole in your pocket.
 
If you have an AUX port...

I use a Jabra Clipper to stream music from my iPhone 3GS running 4.1 through to my Ford Fiesta stereo which is standard and it works like a charm :)

Hope this helps.
 
Can this be done without sending phone calls to the same device?

My car had bluetooth for phone, not music. I would get a bluetooth reciever for my aux jack, but I still want phone calls through the car itself.
 
I've got mine playing music through bluetooth on my honda accord using the Pioneer AVH-P3100DVD. I HAD been playing music through the USB cable, but it looks like 4.1 broke that for me. It also runs phone calls through the bluetooth (automatically pauses the music and switches it to phone when someone calls).
 
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