So, I recently got a 2010 13inch Macbook Pro, replacing my 2006 Macbook, and am loving it with the exception of one thing. Before anyone says anything, yes I knew about the LineIn/Headphone port before I bought the computer, and although it was lame I decided to deal with it, but I'm just curious if there is anything I can do about it. On my 2006 Macbook, I'd record with Garageband with my guitar plugged into the line in, and headphones or speakers plugged into the headphone jack because the Macbook speakers are a little too quiet. On my Macbook Pro, I have to pick one or the other. I realize the MBP switches between "receiving" and "giving" audio through the jack, and I don't think it's quite possible for it to do both at the same time, but this morning I just happened to find a splitter under my desk, so I figured I would ask. Does anyone know if there is a way to add a splitter and get both functions out of the jack?