So I've just got my hands on a pair of headphones with a build in microphone. I borrowed them from a friend, so that's why I'm asking here and not in the store. Now, there's one concern. The headphones have two wires. One for the sound input and one for the microphone. My computer, on the other hand, doesn't. It's a Mac Mini, and they only have one sound input. So does my speakers. On the back of the computer, there's another port, with an icon that looks like two arrows pointing into a circle, if you know what icon i'm talking about. Is there some way to get that to work as a microphone input? I don't know what that port is really, what is it? To fix this problem I've seen that there's USB soundcards with two ports for this purpose, but I would want to know if there's some other way to solve this before I buy something for $36 for a pair of borrowed headphones. Thanks in advance.