There seems to be something funny going on with my 12' PB's Firewire port. It can no longer detect my external harddrive or DVD-RW. It's not something wrong with either of them, or the cable, because I plugged them into a 12' iBook and it worked fine.And yet when I plugged my iPod Nano into the Firewire port, it still charged the Nano. Is there anything else I can do besides call Apple? The computer is about a year old, but it has Applecare. If I have to send it in, will it cost me anything?