Hi Andy,
All the systems are on 10.5.5 and the latest version of Quicktime, I have tested this on 3 mac pros, 4 G5’s, 1 x macbook pro 17″, 2 x macbook, and an older powerbook G4 running and older version of the OS and Quicktime 7.3. All the firewire ports tested function perfectly if a disk drive is plugged in and I have checked the firewire Dv output of the camera I am using by Connecting it directly to the DV input of my DSR 45 deck. Everything is working independently, they just won’t talk to one another. The thing is I rarely work with firewire DV captures, our company has primarily been shooting on XDcam Variations for 2 years so things could have gone wrong a while ago and I wouldn’t have noticed.
Mark