I'm running a RHEL6 as a development desktop with Fedora 14 (multimedia stuff) and Win XP (corporate email and calendars) running on it as KVM VMs. Everything runs great except for audio pass through. Audio works on the RHEL host. Both VMs see sound cards provided by the VM, but no sound is forthcoming. I have tried adding a PCI audio device from the physical host to the Fedora VM, but then it refuses to boot. I remember reading that physical hardware can only be passed through to VMs if it is not in use on the physical host. Any suggestions on how to get audio pass through happening? How can I get the host to "relinquish" the audio device so that a VM can use it? Thanks Michael Hall IT Communications Officer Alice Springs Town Council mhall@xxxxxxxxxxxxxx (08) 8950 0561