LXD vga type console login blocks audio devices in host OS

[selcem-artan]

Hello team,

I have a Ubuntu Desktop VM running named "esa-desktop" on LXD as below. When I launch a console via lxc console --type vga esa-desktop, it launches remote console successfully but also throws below errors and my PC built-in mic and speaker does not work anymore. Could you please help if audio transfer could be disabled?

$ lxc ls
+---------------+---------+------+------+-----------------+-----------+
|     NAME      |  STATE  | IPV4 | IPV6 |      TYPE       | SNAPSHOTS |

+---------------+---------+------+------+-----------------+-----------+
| esa-desktop   | STOPPED |      |      | VIRTUAL-MACHINE | 0         |

$ lxc console esa-desktop --type vga

(remote-viewer:1804033): GLib-GObject-WARNING **: 12:13:06.540: g_object_get_is_valid_property: object class 'GstAutoAudioSink' has no property named 'volume'

(remote-viewer:1804033): GLib-GObject-WARNING **: 12:13:06.567: g_object_get_is_valid_property: object class 'GstAutoAudioSrc' has no property named 'volume'

$ lxd version
5.21.1 LTS

[simondeziel]

Here, testing with spicy (rather than remote-viewer) I have similar warnings:

$ lxc launch images:ubuntu/noble/desktop nd1 --vm -c limits.cpu=2 -c limits.memory=6GiB
$ lxc console -t vga nd1
GSpice-Message: 09:54:19.429: main channel: opened
port 0x589770488300 org.spice-space.webdav.0: opened
port 0x589770488300 org.spice-space.webdav.0: closed
/dev/shm/jack_db-0/__db.001: No such file or directory

(spicy:1214121): GLib-GObject-WARNING **: 09:54:41.215: g_object_get_is_valid_property: object class 'GstAutoAudioSink' has no property named 'volume'
/dev/shm/jack_db-0/__db.001: No such file or directory

(spicy:1214121): GLib-GObject-WARNING **: 09:54:41.221: g_object_get_is_valid_property: object class 'GstAutoAudioSrc' has no property named 'volume'

However, those warnings are consistent with the fact that the VM has no real audio device attached to it:

That said, my host's sound is unaffected by having this VGA console opened.

[simondeziel]

@selcem-artan, could you please indicate how you created that esa-desktop VM?

Also, it'd be useful if you could share the following details on your host machine (I've provided results for my host machine):

$ echo "$XDG_SESSION_TYPE"
wayland

$ cat /etc/os-release 
PRETTY_NAME="Ubuntu 22.04.4 LTS"
NAME="Ubuntu"
VERSION_ID="22.04"
VERSION="22.04.4 LTS (Jammy Jellyfish)"
VERSION_CODENAME=jammy
ID=ubuntu
ID_LIKE=debian
HOME_URL="https://www.ubuntu.com/"
SUPPORT_URL="https://help.ubuntu.com/"
BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
UBUNTU_CODENAME=jammy

$ uname -a
Linux sdeziel-lemur 6.5.0-28-generic #29~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Apr  4 14:39:20 UTC 2 x86_64 x86_64 x86_64 GNU/Linux

Thanks!

[tomponline]

@simondeziel is there a way to invoke the spice client without sound mode?

[simondeziel]

@tomponline not that I could find when looking at both remote-viewer and spicy man pages.

[simondeziel]

@selcem-artan also, once you have the VGA console running, could you check your host's sound configuration and see if there is are new output and input devices showing?

gnome-control-center sound will let you see the sound menu which should look like this:

If if you click on the Output Device and Input Device drop down lists, you should see which devices are currently actives and which are present.

[selcem-artan]

Hello Sİmon and Tom,

I am creating my VM using below; lxc launch images:ubuntu/22.04/desktop esa-desktop --vm -c limits.cpu=1 -c limits.memory=2GiB

I will check for sound setting as you showed

[selcem-artan]

I am sharing "Audio" settings from both my main OS (left), and Ubuntu Desktop VM (right). IN left one, no more selection is available

[simondeziel]

@selcem-artan thanks, so far that doesn't seem to indicate a problem. Could you please share the other bits of information from your host, those from https://github.com/canonical/lxd/issues/13402#issuecomment-2082912230? Those will help us narrow down what it could be.

[simondeziel]

So far, I've been unable to reproduce this issue locally while using the same guest OS. My local environment runs under Wayland (XDG_SESSION_TYPE=wayland).

[simondeziel]

I'll close the issue as I'm unable to reproduce it. @selcem-artan please let us know if you are still experiencing it and share a bit more information about your local environment to help us reproduce and fix it. Thank you

[matthiasch]

I have the same problem. After reading this, I realized it has to do with how the viewer process gets spawned.

As a workaround, I use xdg-open with the socket url, and replaced in "/snap/lxd/current/bin/remote-viewer" this line:

exec unshare -U -r chroot "/var/lib/snapd/hostfs/" "${CMD}" "$@"

with this:

    # Use xdg-open instead of launching the viewer in a new ns
    # must have a valid audio device, e.g.:
    # lxc config set VM_NAME raw.qemu -- "-device intel-hda -device hda-duplex -audio spice"
    xdg-open "$@"
    VIEWER=$(echo "/usr/bin/${CMD} $@" | sed 's/\+/\./g' )
    echo "waiting for viewer to close..."
    echo "VIEWER: $VIEWER"
    
    VIEWER_PID=$(pgrep -f "${VIEWER}")
    echo "VIEWER_PID: $VIEWER_PID"
    
    while [ -n "$VIEWER_PID" ]; do
        VIEWER_PID=$(pgrep -f "${VIEWER}")
        sleep 1s
    done
    
    echo "release socket"
    exit 0

To use the modified script, I mount it over the existing one in the lxd snap: sudo mount --bind ${HOME}/remote-viewer /snap/lxd/current/bin/remote-viewer

With this I have working sound (including mic) in the an ubuntu vm. The vm must have a valid audio device, e.g.: lxc config set VM_NAME raw.qemu -- "-device intel-hda -device hda-duplex -audio spice"

I have attached the complete file: remote-viewer