> What I don't understand is why in the past I have sometimes been able to have both devices
> connected, capture and at the same time save to other firewire device if I only have one
> functioning fw port.
It's not a guaranteed failure. I've been using a DV deck and external FireWire drives simultaneously, with no separate PCI card, for years. But it's not a sure thing, either. It's one of those "at your own risk" deals.
That said, what brand of drive are you using? Some are better than others.
If you have enough storage on your internal drive, you could capture to that and then copy the files over to the external drive for editing. Work around having only one FireWire device at a time.
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