I googled it and found only one meaningful result. It happened to be from another forum. One response to a question almost exactly like yours was that it was possible, but you have to attach the firewire cable to one of the headers on the motherboard instead of on the soundcard (which doesn't have one). Later, the user responded with news of driver and incompatibility problems using that idea. The last post, he/she stated they were going to install new drivers that night. No other posts were made.

I don't have any experience with the way the breakout boxes work. I was under the impression it would use a proprietary cable to connect to the soundcard, but apparently they use a standard firewire header cable. If you already have all those things on hand (x-fi, audigy breakout box, firewire headers), it's worth a try, but otherwise, I wouldn't bother.

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