Hi, since most of us have not working audio in, I'd like to know how about using an USB microphone.
If it comes with OSX drivers, it should work, doesn't it?

Doubt you even need drivers or at least the Griffin iMic I bought on Ebay did not need them so with drivers included it should work for sure, got it for ~$15 for a refurbished model if you go the Ebay route with it look around they go fairly cheap on there.

Thank you, I found it very helpful!

If you say it works oob, I'll buy an iMic too.

Oh it definitely works I use it mainly for my headphones another thing which usually does not work but I tested with the Line-In program and the Mic that is attached to them had no problem using either the line-in or mic-in option the iMic has, plus it is a standard USB device so it will work with any OS that supports USB Audio devices.

Edit: If you plan on using headphones you may want to install the AudioSwitcher it allows you to switch between the various audio options you have works with the inputs as well.