Setting up an audio VM

dpr · August 3, 2021, 9:07pm

Hi,

I am trying to create an audio VM for my bluetooth headphone. I know it should be possible in 4.1, but I can’t find any documentation on how to do it. Can anyone shed some light into it?

Many thanks

Quser59 · August 3, 2021, 9:11pm

No official documentation AFAIK, but advice here may be of help:
https://linuxadministration.us/bluetooth-headset-with-qubes/

marmarek · August 3, 2021, 9:34pm

There is indeed no documentation about that yet. But there is salt formula to set it up: qubes-mgmt-salt-dom0-virtual-machines/sys-audio.sls at master · QubesOS/qubes-mgmt-salt-dom0-virtual-machines · GitHub (not tested too much…)

marmarek · August 3, 2021, 9:35pm

@fepitre can you provide commands to set it up?

dpr · August 3, 2021, 10:47pm

Thanks for the reply. I managed to set sys-audio up using the salt formula provided, however it just broke all audio and now I can’t hear anything I will keep trying to fix it and will post any updates here.

dpr · August 5, 2021, 3:33am

Still no luck in setting it up, can you provide some instructions @fepitre? This is the only thing missing so I can make Qubes my main OS.

dpr · August 5, 2021, 4:30am

I would like to point out that there seems to be a bug with the default audio vm salt files. If I install it, it will not let me shutdown sys-audio if it is being used as an audio qube for other vms. While this is expected behavior, what is not expected is that it considers sys-audio to be the audio VM for itself, so sys-audio can not be shutdown unless sys-audio is already shutdown

fsflover · August 5, 2021, 9:09am

But why is this expected? I expect that I can shut it down and have no sound.

dpr · August 5, 2021, 9:13am

It’s the same behavior that is implemented with network vms, that’s why I would expect this.

fepitre · August 7, 2021, 8:50am

I can provide instructions later in the next week.

dpr · August 14, 2021, 11:02am

Any news on this topic?

fepitre · August 14, 2021, 12:42pm

Unfortunately no, I’m currently busy with prior tasks.

dpr · August 17, 2021, 10:48pm

For those that might stumble upon this thread in search for a solution for using bluetooth headphones with Qubes, I solved this temporarily by purchasing a bluetooth adapter into 3.5mm audio jack. Just make sure to get one that supports TX mode, like this one

GammaSQ · August 29, 2021, 4:26pm

So I got myself an audio-vm using

qubesctl state.sls qvm.sys-audio

removed pci-devices, set it’s audiovm to None (because the system would freeze on starting sys-audio and I think that was because of circular audiovm definitions?)
I installed qubes-audio-daemon from qubes-vm-*-current-testing

When I start a Qube which has audiovm set to sys-audio and run

pactl-simple-vchan [xl-id] [name]

I get an audio-stream which is visible in pavucontrol and, as pci-devices where still connected, audible.

My main usecase is using usb-audio and bluetooth without any touching dom0. When I connect my usb-headset to sys-audio, it is correctly detected and shows up in pavucontrol. However, when I use pactl-simple-vchan, I hear nothing. pavucontrol shows audio playback via the headset (the sound-bar jumps back and forth).

Even weirder, starting playback inside sys-audio works perfectly fine and keeps on working if I start pavucontrol while playback is audible.

Am I missing some pulseaudio/alsa/modprobe setup?

kef · September 19, 2021, 6:54am

Just got this working.

Roughly the steps that I can recall now were to download the template vm that the sys-audio salt state uses - the salt states can be found here btw:

github.com

QubesOS/qubes-mgmt-salt-dom0-virtual-machines/blob/master/qvm/sys-audio.sls

# -*- coding: utf-8 -*-
# vim: set syntax=yaml ts=2 sw=2 sts=2 et :

##
# qvm.sys-audio
# ===========
##

{% from "qvm/template.jinja" import load -%}

{% if salt['pillar.get']('qvm:sys-audio:name', 'sys-audio') != salt['pillar.get']('qvm:sys-gui:name', 'sys-gui') %}

{% set vmname = salt['pillar.get']('qvm:sys-audio:name', 'sys-audio') %}

{% load_yaml as defaults -%}
name:          sys-audio
present:
  - label:     black
  - mem:       400
prefs:

This file has been truncated. show original

and fedora-33-xfce is the template vm it uses.

Once the state is run and the sys-audio vm created the template vm needs to have the qubes-core-admin-client rpm installed - this provides the qvm-start-daemon python script that is used to start the pacat processes for each vm audio client.

Next, startup the sys-audio vm and create ~/.config/autostart entries for qvm-start-daemon and pulseaudio:

eg. ~user/.config/pulseaudio.desktop
[Desktop Entry]
Name=Pulseaudio
Comment=Starts Pulseaudio
Icon=qubes
Exec=pulseaudio
Terminal=False
Type=Application
NotShowIn=KDE;

eg. ~user/.config/qvm-start-daemon.desktop
[Desktop Entry]
Name=Qubes Guid/Pacat
Comment=Starts GUI/AUDIO daemon for Qubes VMs
Icon=qubes
Exec=qvm-start-daemon --all --watch
Terminal=False
Type=Application
NotShowIn=KDE;

Next there are some problems with the policy that the salt state creates. It’s a bit of a pain to work though but the popup notifications are helpful - the policy is defined in /etc/qubes/policy.d/50-sys-audio.policy on dom0

I’d paste it here but tbh I’m a bit lazy and it’s on dom0

Finally, each vm needs to have the audiovm adjusted w/

eg. qvm-prefs audiovm sys-audio

kef · September 19, 2021, 7:01am

Oh yeah, and I went into services on sys-audio and added the audiovm services.

kef · September 19, 2021, 7:07am

Oh, and those .desktop files are in ~user/.config/autostart

dpr · September 19, 2021, 9:30am

Thanks for the instructions, I will try and post my results here.

Edit: I got a working audioVM, after a lot of troubleshooting and banging my head against a wall.
I will try to optimize the process and will post clearer instructions here when I have the time.

augsch · October 26, 2021, 4:04pm

I was able to run the salt formula and create sys-audio.

I successfully had sys-audio handling my soundcard, but I cannot create pulseaudio streams to it.
I used pacat-simple-vchan (dom-id of sys-audio) sys-audio in appvms, and most of them said command not found.

So I installed qubes-audio-daemon in my templates of my appvms. Now the command could be run, but nothing happened. No new “Application” stream in sys-audio. After I set qubes-prefs default_audiovm sys-audio, newly created qubes didn’t created streams in dom0, but not in sys-audio either, even after I had rerun pacat-simple-vchan.

So could anyone help me please? Thanks in advance.

augsch · October 28, 2021, 4:46am

Update:Now I’m able to see virtual streams in sys-audio pulseaudio control panel.

However, playing songs is impossible because the pulseaudio doesn’t automatically update the sound buffer. I made this guess because everytime I click at any botton of the pavucontrol window, the sound will update a bit and replay that bit again and again(making a lot of noise). As long as I click quick enough, I can tell from the rather scratchy and intermittent sound that the song is being played.

So how can I fix that? Thanks.