Hi, I've setup couple VMs and different Linux distros.

 

I have EVGA GTX 960 SC being passed through to guest VM.

 

My GPU works great with passthrough and Nvidia  drivers, however GPU HDMI audio stutters and absolutely

not playable and even stutters youtube video if used. 

I first noticed it with sytem sounds when they would stutter and it feels like it repeats and woudn't stop

until pulseaudio -k is called.

 

I am using Q35 machine with OVMF bios I tried Arch Linux and Ubuntu both had same issue.

However audio seems to be working on SeaBios with Q35. 

Also when using SeaBios I can see 5.1, 7.1 and Stereo (this is one I use) settings for my sound, but with OVMF

it shows only  Stereo (2.0) setting. However I would prefer not to use SeaBios as it seems more problematic overall from

what I've read about it.

I've tried proxmox and Fedora server and it had same issue with audio, but SeaBios wouldn't work with my GPU at all on it

 

I am planning to test this other OS (Mac, Win) maybe I can do some setup from Linux side to fix it, if it is OS issue.

 

Here is  XML from Ubuntu with SeaBios with working audio:

 

<domain type='kvm' xmlns:qemu='http://libvirt.org/schemas/domain/qemu/1.0'>
  <name>Ubuntu</name>
  <uuid>30be4590-7338-1f15-1a15-67910c87f325</uuid>
  <metadata>
    <vmtemplate name="Custom" icon="ubuntu.png" os="ubuntu"/>
  </metadata>
  <memory unit='KiB'>4194304</memory>
  <currentMemory unit='KiB'>4194304</currentMemory>
  <memoryBacking>
    <nosharepages/>
    <locked/>
  </memoryBacking>
  <vcpu placement='static'>8</vcpu>
  <cputune>
    <vcpupin vcpu='0' cpuset='0'/>
    <vcpupin vcpu='1' cpuset='1'/>
    <vcpupin vcpu='2' cpuset='2'/>
    <vcpupin vcpu='3' cpuset='3'/>
    <vcpupin vcpu='4' cpuset='4'/>
    <vcpupin vcpu='5' cpuset='5'/>
    <vcpupin vcpu='6' cpuset='6'/>
    <vcpupin vcpu='7' cpuset='7'/>
  </cputune>
  <os>
    <type arch='x86_64' machine='pc-q35-2.3'>hvm</type>
  </os>
  <features>
    <acpi/>
    <apic/>
  </features>
  <cpu mode='host-passthrough'>
    <topology sockets='1' cores='8' threads='1'/>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='writeback'/>
      <source file='/mnt/user/VirtualMachines/Ubuntu/vdisk1.img'/>
      <target dev='hdb' bus='virtio'/>
      <boot order='1'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x04' function='0x0'/>
    </disk>
    <controller type='usb' index='0' model='ich9-ehci1'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x02' function='0x7'/>
    </controller>
    <controller type='usb' index='0' model='ich9-uhci1'>
      <master startport='0'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x02' function='0x0' multifunction='on'/>
    </controller>
    <controller type='sata' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
    </controller>
    <controller type='pci' index='0' model='pcie-root'/>
    <controller type='pci' index='1' model='dmi-to-pci-bridge'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/>
    </controller>
    <controller type='pci' index='2' model='pci-bridge'>
      <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x03' function='0x0'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:00:55:b6:d2'/>
      <source bridge='br0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target port='0'/>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <channel type='unix'>
      <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/Ubuntu.org.qemu.guest_agent.0'/>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <vendor id='0x045e'/>
        <product id='0x0084'/>
      </source>
    </hostdev>
    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <vendor id='0x046d'/>
        <product id='0xc31c'/>
      </source>
    </hostdev>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x05' function='0x0'/>
    </memballoon>
  </devices>
  <qemu:commandline>
    <qemu:arg value='-device'/>
    <qemu:arg value='ioh3420,bus=pcie.0,addr=1c.0,multifunction=on,port=2,chassis=1,id=root.1'/>
    <qemu:arg value='-device'/>
    <qemu:arg value='vfio-pci,host=01:00.0,bus=pcie.0,multifunction=on,x-vga=on'/>
    <qemu:arg value='-device'/>
    <qemu:arg value='vfio-pci,host=01:00.1,bus=pcie.0'/>
  </qemu:commandline>
</domain>

 

Here is XML from Arch Linux VM with  OVMF

 

<domain type='kvm'>
  <name>ArchBox</name>
  <uuid>93bde4f2-cedf-8234-79fc-1b75c54d2ea8</uuid>
  <metadata>
    <vmtemplate name="Custom" icon="arch.png" os="arch"/>
  </metadata>
  <memory unit='KiB'>4194304</memory>
  <currentMemory unit='KiB'>4194304</currentMemory>
  <memoryBacking>
    <nosharepages/>
    <locked/>
  </memoryBacking>
  <vcpu placement='static'>8</vcpu>
  <cputune>
    <vcpupin vcpu='0' cpuset='0'/>
    <vcpupin vcpu='1' cpuset='1'/>
    <vcpupin vcpu='2' cpuset='2'/>
    <vcpupin vcpu='3' cpuset='3'/>
    <vcpupin vcpu='4' cpuset='4'/>
    <vcpupin vcpu='5' cpuset='5'/>
    <vcpupin vcpu='6' cpuset='6'/>
    <vcpupin vcpu='7' cpuset='7'/>
  </cputune>
  <os>
    <type arch='x86_64' machine='pc-q35-2.3'>hvm</type>
    <loader type='pflash'>/usr/share/qemu/ovmf-x64/OVMF-pure-efi.fd</loader>
  </os>
  <features>
    <acpi/>
    <apic/>
  </features>
  <cpu mode='host-passthrough'>
    <topology sockets='1' cores='8' threads='1'/>
  </cpu>
  <clock offset='utc'>
    <timer name='rtc' tickpolicy='catchup'/>
    <timer name='pit' tickpolicy='delay'/>
    <timer name='hpet' present='no'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/bin/qemu-system-x86_64</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='writeback'/>
      <source file='/mnt/user/VirtualMachines/ArchBox/vdisk1.img'/>
      <target dev='hdb' bus='virtio'/>
      <boot order='1'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x04' function='0x0'/>
    </disk>
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='/mnt/user/Software/images/archinstall.iso'/>
      <target dev='hda' bus='usb'/>
      <readonly/>
      <boot order='2'/>
    </disk>
    <controller type='usb' index='0' model='nec-xhci'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x02' function='0x0'/>
    </controller>
    <controller type='sata' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1f' function='0x2'/>
    </controller>
    <controller type='pci' index='0' model='pcie-root'/>
    <controller type='pci' index='1' model='dmi-to-pci-bridge'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x1e' function='0x0'/>
    </controller>
    <controller type='pci' index='2' model='pci-bridge'>
      <address type='pci' domain='0x0000' bus='0x01' slot='0x01' function='0x0'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x03' function='0x0'/>
    </controller>
    <interface type='bridge'>
      <mac address='52:54:00:f4:ea:67'/>
      <source bridge='br0'/>
      <model type='virtio'/>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x01' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target port='0'/>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <channel type='unix'>
      <source mode='bind' path='/var/lib/libvirt/qemu/channel/target/ArchBox.org.qemu.guest_agent.0'/>
      <target type='virtio' name='org.qemu.guest_agent.0'/>
      <address type='virtio-serial' controller='0' bus='0' port='1'/>
    </channel>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x01' slot='0x00' function='0x0'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x05' function='0x0'/>
    </hostdev>
    <hostdev mode='subsystem' type='pci' managed='yes'>
      <driver name='vfio'/>
      <source>
        <address domain='0x0000' bus='0x01' slot='0x00' function='0x1'/>
      </source>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x06' function='0x0'/>
    </hostdev>
    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <vendor id='0x045e'/>
        <product id='0x0084'/>
      </source>
    </hostdev>
    <hostdev mode='subsystem' type='usb' managed='yes'>
      <source>
        <vendor id='0x046d'/>
        <product id='0xc31c'/>
      </source>
    </hostdev>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x02' slot='0x07' function='0x0'/>
    </memballoon>
  </devices>
</domain>

 

This is my audio on working scenario

00:02.0 Audio device: NVIDIA Corporation Device 0fba (rev a1)
Subsystem: eVga.com. Corp. Device 2962
Flags: bus master, fast devsel, latency 0, IRQ 23
Memory at fe680000 (32-bit, non-prefetchable) [size=16K]
Capabilities: [60] Power Management version 3
Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [78] Express Root Complex Integrated Endpoint, MSI 00
Capabilities: [100] Advanced Error Reporting
Kernel driver in use: snd_hda_intel

 

This is my audio on non-working scenario

 

02:06.0 Audio device: NVIDIA Corporation Device 0fba (rev a1)
Subsystem: eVga.com. Corp. Device 2962
Flags: bus master, fast devsel, latency 0, IRQ 20
Memory at d3004000 (32-bit, non-prefetchable) [size=16K]
Capabilities: [60] Power Management version 3
Capabilities: [68] MSI: Enable- Count=1/1 Maskable- 64bit+
Capabilities: [78] Express Endpoint, MSI 00
Kernel driver in use: snd_hda_intel
Kernel modules: snd_hda_intel

 

 

No one had similar issues?

 

I also tried newer version of qemu 2.5.0 on Ubuntu 16.04 Server and I am getting

Unable to determine the device handle for GPU error from nvidia-smi on both OVMF and SeaBIOS

 

UnRaid 6.2 Beta has same issue with audio with OVMF

 

 

I am having this issue as well. 

I'm running 3 windows 10 vm's

1-OVMF, i440fx2.5, evga 960ssc

2-OVMF, i440fx2.5, evga 960sc

3-SeaBIOS, i440fx2.5, asus 750ti

 

They all appear to be having this issue.