[kismetcapitan]

my car stereo is set up to run only off of an iPod Touch 2G, by using a Component AV cable. iPod to cable, cable to JL Audio line driver w/volume control (because the Component AV cable disables volume control wtf?), then line driver to my car's amplifiers and speakers. USB goes to a USB charger.

Works great - I get music and my iPod charges.

However, my iPhone 3GS is soon arriving, and I plan to use it in exactly the same way. So for listening to music, should work the same.

But I'd like to send/receive calls as well. In phone mode, will the iPhone output audio through the Component AV cable? Or revert to the built-in speaker?

And of course, there's no mic-in with the Component AV. So will the iPhone just use the built-in mic, or will it use a plug-in mic - I'd just plug in a direction capsule mic on top, or a cabled mic that I could clip to my lapel.

I suppose I could pair a bluetooth headset and use that to talk. But the best hands-free car solutions require the minimum number of steps. If I can get the audio out of the Component AV cable, and sound in through a mic that I plug in when I mount the iPhone in its cradle, then if a call comes in I just need to swipe and then talk, instead of grabbing for a headset.

[kismetcapitan]

well, I've got my iPhone, so plugged it into my car. Audio out goes through the Component AV cable when a call is received. Audio in works through the built-in mic, which isn't good enough for a decent hands-free conversation because the distance from mouth to phone is too far to be really clear. And leaning in towards the dash while driving probably isn't too safe.

Plugging in headphones, bypasses the C-AV cable, and all input-output goes through the headphones. Not exactly handsfree, unless you leave your headphones in your ears all the time while driving.

I need to get my hands on a capsule mic, plug it in and see if it disables audio output (i.e. if plugging it in makes the iPhone think that headphones are in as well). If it doesn't, this whole thing will work.

Otherwise, there's just a bluetooth headset option, or the option of getting very loud and clear audio through the speakers when someone calls you, but they will barely be able to hear you....