This may be of help.
For the last year all has been well running Windows 10 with the legacy 1394 drivers. Two weeks ago I had a windows update and I started to suffer constant drop-outs - the FW Active light would just turn off. Trust me, I uninstalled and reinstalled many things - even the nVidia display drivers - but the problem remained.
In desperation I switched to the old VIA 1394 driver in my Windows 10 list and, after 24 hours, everything is still working. (I tried this driver when I had the same problem after a Windows update a year ago. Back then it didn't help - most odd).
I am not looking forward to the next Windows update.
OK so than idea failed shortly after I posted my comment. However, having installed the VIA drivers and then going back to the legacy drivers I have managed 4 hours editing im Adobe Premiere without a single drop-out.