computer goes into kernel panic while tethered

I have a Intel Xeon 2.66 GHz 8GB Mac Pro Tower. The kernel is Darwin v8.9.1. OS X 10.4.10. While I have my DSLR tethered to it through the firewire port on either the front of the computer or the back of the monitor; the system goes into kernel panic; inconsistently.

In other words this does not happen every time the camera (canon 1Ds Mark II or 5D) is tethered to the computer. I have tried many different cords and all of the different ports on the computer. Also, I have not been able to get a P25+ connected to the software, even though the back was being powered by the firewire cord. P backs do not send the computer into kernel panic and they work inconsistently. I plugged the same set up P25+ and cord into my Mac Book Pro and no issues. It will link up to the software tethered no problems. Usually the panic happens while I am using Capture One. I reinstalled Capture One several times.

Then I took the computer into the genius bar. They did a complete system diagnostic test on the hardware and found nothing wrong with it physically. They then reinstalled OS X. It still went into kernel panic. They told me that their best guess was that the Intel Xeon chip was having a conflict with the Canon DSLR while tethered. Once again this does not happen every time. And it does happen most consistently while I am working in C1.

Also the USB ports and firewire ports are functioning inconsistently with different DSLR cameras/readers.

Has anyone had ANY experience like this?

Thanks!!