canon mvx 460 pc detection problem

Having not long owned this cam..i have only just got around connecting it to my pc...
the first time it worked and was recognised by windows xp...(connection via firewire and pci card.
anyway...now i come to it..and it isnt detected by windows..or any recording media.

(have tried on other pc as well....same result..)
on the lcd displayon the camcorder?..does the dv-in normally flash while in player mode..and if so..what does it indicate?
sometimes it does..sometimes it doesnt..very confusing...

ive also tried the usb port on the cam...for stills..the same result..it isnt detected by windows..
ive checked the settings... (the only ones i can find .. and they seem correct according to the booklet
cheers
Geoff.