HI.
Always keep firewire cable connected to computer or you may end up like I did.I inserted 6pin end of cable the wrong way round due to socket getting a bit slack,and believe me it can go in the wrong way round.The result is a damaged firewire camera connection.As camera (Panasonic NV-7) was 5yrs old it was more economicale to buy a new camera(Panasonic GRS-400) even though the rest of camera was working o/k.
I sometimes have computer on but always have camera off when connecting firewire cable to camera.
After editing project I export back to DV tape (to keep as a master copy).Then I burn to disc useing another firewire cable(4pin either end) connected between camera and a Panasonic DVD Recorder.When disc is full I finalise it on the DVD recorder.Camera and DVD recorder are always off until cable is connected.
Hope this might help someone not to make my mistake.
Robieboy