alright just got a macbook the other day. and i heard that this has a built in mic already. so i plugged a headphones so i can here myself better. then after, i spoke to the mic but i cant here myself. so i went to system preferences then sound then input. internal microhpone is highlighted but still nothing. i can see the bar moving so it seems working. but still i cant here myself. same thing when i plug my guitar directly to the line in port. i cant here anything but the bar from the sound setting is moving.. i really need some help.