NOT SEEING CANON HV20

My G-5, OS 10.5.8, FCP 6.0.6, can not see the canon HV20. I am connected out through Cannon HDV/DV out and go into a 400 connection in back of the Mac. The computer does not see the camera. Took it to Burbank Mac. They saw the camera on their FCP 7 system using the 400 connection. I check to make sure I took test footage in HD. I check to make sure the output was HD. Still the G-5 does not see the camera. Apple suggested going to "about this Mac, fire wire". No camera. If I plug the camera using the 400 fire wire cable into the computer and then unplug the camera, the computer does not say a device was unplugged. Any advice?
Ermanno

Have you tried plugging anything else into that same FW port to confirm that the port is functioning correctly?

debe