This is AWESOME!!! I think the line in port can be a little misleading. I bought a $20 headset that said it was Mac compatible. Well the line in port does not provide power for the device so you have to have a USB Audio Adapter. Which you can find for about $20. So at this point just spend the money to get a headset with the USB Audio Adapter. Which I didn't want to do since I had an orginal iMic sitting around. Well guess what the iMic didn't work for what ever reason. The MacBook Pro sees it but neither the line in or out on the iMic work. UNTIL... I downloaded and installed LineIn!!! Thanks guys, this bit of software rocks!!!