Googled, see this exact problem a lot and only "solution" seems to be update firewire card driver. Found thread here with same solution, but that was HP computer and solution was link to HP driver. My firewire port in on motherboard, ASUS P7P55-M.
Computer is brand new and was built to do hd to blu-ray, came with Cyberlink powerdirector. Hard to believe deficient driver. Googled "p7p55-m driver" and got "we found driver for your p7p55-m" from third party driver update software folks but don't trust "we found driver." I have been to ASUS and find a bewildering array of drivers for the motherboard, none specific to firewire, and hesitate to mess with the motherboard. See no way to contact ASUS.
I have run programs to update drivers, been to Microsoft and to Sony for any updates, downloaded and installed all possible suspects, even upgraded from powerdirector from 7 to 9, all with little hope and no result. Ideas? I'm no tech whiz and am new to editing, so I'm hoping for suggestions/solutions that don't make my eyes glaze over. (for reference, they glazed over reading the readme file here - no clue how to provide a screenshoot (NA here) or Direct X diagnostics, and what's avatar?) Thanks -