hmmm...i've never been able to get this to work, but can you try changing the IRQ for that device? you would go the resources tab of the device properties and uncheck automatically configure (if it is not greyed out) and change the interrupt to one that is not being used...
like i said i have never been able to do this with mine, might be the copy of w2k i have or a trait inherent to many of the devices i have that won't allow me to change the IRQ, despite countless hours of research i have done to find a way around that. YMMV and good luck, god speed