Hi Michael Mayers,
I'm having the same problem with a firewire audio card, high latency and audio glitches,
the machine is almost the same,
Intel® SC5600BASE Case
Intel® Workstation Board S5520SC
2 x Intel® Xeon® CPU E5620 @ 2.40GHz
4 x KINGSTON KVR1333D3D4R9S/4G total 16Gb RAM DDR3 1333Mhz ECC
2 x SEAGATE BARRACUDA 7200.11 1.5TB RAID 1
SAPPHIRE RADEON HD 5670 512MB
WIN 7 PROFESSIONAL OEM 64BIT
SATA DVD Burner
I found big latency issue on the following kernel modules hal.dll and ntoskrnl.exe, i was supposing that an IRQ sharing was the origin of the problem.
have you solved the problem in any way?
have you found how to assign IRQ manually?