FW400 port does not recognize any peripherals

I recently bought a used (early 2008) MBPro 15" 2.5 SR to do some video editing. Unfortunately it will not recognize my Sony DV camera, or an external HD connected via FW400 or my 12" PB booted in target disk mode. The camera and the hard drive both mount instantly on my 12" PB and a friends 15" PB.

Also, when I check the Firewire status under System Profiler all it says is:
Warning: Unable to list FireWire devices (in red).
This is regardless of what is connected to the port or if nothing is connected to the port.

I have tried rebooting the PRAM and changing the Firewire port's network preference to OFF as recommended by this post:
http://forums.macrumors.com/showthread.php?t=296702


Any last ideas before taking the machine into Apple?
Thanks