I've been here in London for over two weeks and going crazy because Vegas 7 (trial) on my laptop could not see my FX1. I knew my setting were right - I have had the FX1 for over 20 months and have been editing HDV since most thought HDV meant "Harriet Does Vegas."
I knew my OHCI card was compliant (and assumed the cable good) as all worked fine with the SDV Canon. Finally trying everything from scratch I went out and bought an expensive ($40 in London!!!) a new 4 to 4 Firewire cable and walla!
Two of my cheaper Firewire cables work with SDI but not HDV. So beware.
Michael