Microphone stuck & undetachable (GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown)

[nil0x42]

Qubes OS version:

R4.0

Affected component(s):

microphone
qvm-device

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Steps to reproduce the behavior:

My initial goal was to attach microphone automatically to 'videochat' qube, so i did the following:

[user@dom0 ~]$ qvm-shutdown videochat
[user@dom0 ~]$ qvm-device mic attach --persistent videochat dom0:mic
[user@dom0 ~]$ qvm-start videochat

No error, here i was thinking that everything was OK, because qvm-device mic list showed that my microphone was used by 'videochat', and sys-usb's tray icon said the same:

[user@dom0 ~]$ qvm-device mic list
BACKEND:DEVID  DESCRIPTION  USED BY
dom0:mic       Microphone   videochat

After starting 'videochat' qube, my microphone was NOT detected.
I then rebooted my machine in order to see if it resolves the issue, and after that, the mic was shown as attached to videochat as expected, but still not working.
So i resolved to undo the persistent attach as shown here:

[user@dom0 ~]$ qvm-device mic detach videochat dom0:mic
Can not remove a persistent attachment from a non halted vm

[user@dom0 ~]$ qvm-shutdown videochat

[user@dom0 ~]$ qvm-device mic detach videochat dom0:mic
Failed to attach microphone: g-dbus-error-quark: GDBus.Error:org.freedesktop.DBus.Error.ServiceUnknown: The name org.qubesos.Audio.videochat was not provided by any .service files (2)

[user@dom0 ~]$ qvm-device mic list
BACKEND:DEVID  DESCRIPTION  USED BY
dom0:mic       Microphone   videochat

Now, i am totally stuck in that situation, the microphone is stuck in videochat, i cannot detach it, and even in videochat qube it doesn't works.

Expected behavior:

The microphone works when attached with '--persistent' argument, and can then be detached.

Actual behavior:

The micropohone is stuck as 'persistently attached', and doesn't work.

General notes:

I think it's a minor issue that persistent attach didn't worked as expected. For me, the real issue is being stuck in a state where my microphone is 100% unusable.

Note: before trying to to 'persistent attach' of my microphone, it worked fine by manually attaching it to any qube from sys-usb tray icon.

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Related issues:

[nil0x42]

Update: i just resolved my issue with a dirty hack, manually edited /var/lib/qubes/qubes.xml, and set mic device to null (<devices class="mic"/>) in videochat qube.
After a reboot, everything seems OK, qvm-device mic list's output shows that mic is not in use, and a can attach and detach my microphone manually again.

[nil0x42]

Update: i just resolved my issue with a dirty hack, manually edited /var/lib/qubes/qubes.xml, and set mic device to null (<devices class="mic"/>) in videochat qube.
After a reboot, everything seems OK, qvm-device mic list's output shows that mic is not in use, and a can attach and detach my microphone manually again.