Mac Tower 1,1 Intel With intermittent Sync issues

I have a client I’ve set up with BoinxTv. She has a Mac Tower 1,1 2.66 Dual.
Here is bus speed
System Bus Speed: 1.33 GHz Cache Bus Speed: 2.66 GHz (Built-in)
Details: 1.33 GHz 64-bit dual independent frontside buses.

Is that enough bus speed?

She intermittently gets audio/video sync problems. I had her switch to recording on the internal drive because I thought the external was the issue. There are 2 identical firewire cameras coming into the computer. If the cameras are coming in on different firewire computer inputs, is there a chance they are sharing the same bus? How can I check this?
Any other ideas as a solution?

Thanks…Rick Savage
Savage Tunes A/V