Bug 848927

Could you attach Windows_7.xml file? Sound should just work if the domain is properly configured to use spice (of course, it only works iff spice client is connected to the domain). If it uses VNC, it should also work if the VNC client supports audio over VNC extension. If it doesn't, the only way is to set vnc_allow_host_audio = 1 in /etc/libvirt/qemu.conf. I would recomend using spice.

Requested xml is below.  I have verified sound also works in spice.  This bug was clearly mistitled by me.  It's not that sound doesn't work, it's that sound doesn't work with the default virt-manager vnc (which is also the default viewer).  

If that is acceptable behavior, perhaps there should be a UI warning on the audio device when trying to configure without spice channels and with a vnc_allow_host_audio = 0 value. Or perhaps spice should just be the default viewer.

***I should also note, I noticed behavior that is contrary to what is being said about vnc.  When I execute the following:

1. I set vnc_allow_host_audio = 1 in /etc/libvirt/qemu.conf
2. Restart libvirtd
3. Start up a Win 7 VM through libvirt with vnc as the viewer
4. Use Tigervnc, which I know to support audio

Audio still does not get passed to host.***

<domain type='kvm'>
  <name>Windows_7</name>
  <uuid>ee9de63c-4cb9-f9c6-84fd-3d0db647fab7</uuid>
  <memory unit='KiB'>2097152</memory>
  <currentMemory unit='KiB'>2097152</currentMemory>
  <vcpu placement='static'>1</vcpu>
  <os>
    <type arch='x86_64' machine='rhel6.3.0'>hvm</type>
    <boot dev='hd'/>
  </os>
  <features>
    <acpi/>
    <apic/>
    <pae/>
  </features>
  <clock offset='localtime'>
    <timer name='rtc' tickpolicy='catchup'/>
  </clock>
  <on_poweroff>destroy</on_poweroff>
  <on_reboot>restart</on_reboot>
  <on_crash>restart</on_crash>
  <devices>
    <emulator>/usr/libexec/qemu-kvm</emulator>
    <disk type='file' device='disk'>
      <driver name='qemu' type='raw' cache='none'/>
      <source file='/var/lib/libvirt/images/Windows_7.img'/>
      <target dev='hda' bus='ide'/>
      <address type='drive' controller='0' bus='0' target='0' unit='0'/>
    </disk>
    <disk type='file' device='cdrom'>
      <driver name='qemu' type='raw'/>
      <source file='/home/jscalia/Share/ISO/en_windows_7_ultimate_x86_dvd_x15-65921.iso'/>
      <target dev='hdc' bus='ide'/>
      <readonly/>
      <address type='drive' controller='0' bus='1' target='0' unit='0'/>
    </disk>
    <controller type='usb' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x2'/>
    </controller>
    <controller type='ide' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/>
    </controller>
    <controller type='virtio-serial' index='0'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x06' function='0x0'/>
    </controller>
    <interface type='network'>
      <mac address='52:54:00:1c:f8:74'/>
      <source network='default'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
    </interface>
    <serial type='pty'>
      <target port='0'/>
    </serial>
    <console type='pty'>
      <target type='serial' port='0'/>
    </console>
    <input type='tablet' bus='usb'/>
    <input type='mouse' bus='ps2'/>
    <graphics type='vnc' port='-1' autoport='yes'/>
    <sound model='ac97'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/>
    </sound>
    <video>
      <model type='vga' vram='9216' heads='1'/>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/>
    </video>
    <memballoon model='virtio'>
      <address type='pci' domain='0x0000' bus='0x00' slot='0x05' function='0x0'/>
    </memballoon>
  </devices>
</domain>

Enabling vnc_allow_host_audio requires prerequisites on the host to actually work (qemu using the correct group, pulseaudio not running ...) so this approach is not really usable.

I'm moving this bug on virt-manager to see if it's feasible to add a warning about audio not working with the default VNC video console as Joseph suggested. I recommend using spice video, where audio works out-of-the-box.

Actually nowadays gtk-vnc actually supports audio streaming, so changing this to track that as an RFE

While gtk-vnc supports audio streaming, I think in practical application very few people will use it, as this type of desktopy case is what spice is suited for. So closing this as DEFERRED, but if someone shows up with a patch I'll consider it