I've never tried using the built in line in, but I've used the Griffin imic as a line in on my ibook. The sound quality is so so, but its good enough for FM, since its only about $40 US.
Its been a bit quiet on the mac forum these days.
I've been trying to use the minis Line in, to use the radio on my phone as an input, i've checked the sound settings and its see's it but will not output the sound. I'm using a stereo jack from the phone to the mini.
Am i doing something wrong?
I did no searching.
Will give it a try.
That program works well, no hiss at all, now i can have radio in the car(albeit not the best quality but good enough), and the added bonus of handsfree mobile through the mac/car speakers.