Is this possible?

If you are wanting to output audio through that bottom port, the simple answer is no.

 

Then, as I said, no. Not with the music app. If you use something like Google music, pandora, or any of those you will still have control over that specific app via your idevice.

 

I thought you could output sound through the 30 pin. That's how 99% of iHomes and other media extension devices work, anyway. I would double check your facts.

 

I haven't seen anything yet that outputs audio via the USB 30 pin cord. All I've seen is either direct 30 pin dock connection on a device or some type of adapter. But never with the normal included or aftermarket USB cord.

 

You CAN output sound. What I am saying is that if his head unit in his car is made to control the iPhone through the head unit, there is nothing he can do to stop the music app from giving you the "device plugged in" (or something similar, can't remember exactly what it is) message. He could alter the cable such that it will do nothing more than charge, but at that point he won;t (ever) be able to stream audio over that cable.

 

Yes you can plug the 30 pin dock connector to a USB Radio and play music through the iPod. You however can not control the music with iPod controls you will have to use the Radio to control music. Now with Pandora or other music app you can control the music form your iPod.

 

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