Q4OS Forum

bin

Member

From: U.K.

Registered: 2016-01-28

Posts: 1,333

Untangling pulseaudio and kmix problem

Hardware is a plain jane desktop PC from 2012 - intel chipset i3220.
Standard intel audiio chip

Sound is via HDMI to speakers on monitor.

I have been driven round the twist with Pulseaudio vanishing from kmix so thought I'd use some lockdown time to try to nail this.

Installed system is fresh TDE Centaurus with latest updates - excluding the latest q4os updates as I did see the volumes issue after initial install and update.

After new install, updates excluding q4os, shutdown and re-start Pulseaudio has vanished from kmix right click Select Channel - this has been reported before.

If I close kmix then open it again from menu, Pulseaudio is back in the Select Channel and will stay there between logouts. If I shut down and re-start we are back to square 1. This can be reproduced ad nauseam on hardware but is not seen in a VM.

kmixrc immediately after a fresh start contains

AllowDocking=true
Autostart=true
DockIconMuting=false
Labels=true
MasterMixer=ALSA::HDA_Intel_PCH:1
MasterMixerDevice=0
Menubar=true
Orientation=Horizontal
Position=480,324
Size=960,432
Tickmarks=true
TrayVolumeControl=true
ValueStyle=None
Visible=false
starttdeRestore=true

[0]
Mixer_Name_Key=HDA Intel PCH
View.input.Devs=5
View.output.Devs=10
View.switches.Devs=7

[1]
Mixer_Name_Key=USB Device 0x46d:0x809
View.input.Devs=1
View.output.Devs=10
View.switches.Devs=7

[2]
Mixer_Name_Key=USB Device 0x46d:0x809
View.input.Devs=1

After close and open kmix it you can select master channel pulseaudio and it becomes

AllowDocking=true
Autostart=true
DockIconMuting=false
Labels=true
MasterMixer=ALSA::PulseAudio:1
MasterMixerDevice=0
Menubar=true
Orientation=Horizontal
Position=935,298
Size=960,432
Tickmarks=true
TrayVolumeControl=true
ValueStyle=None
Visible=false
starttdeRestore=true

[0]
Mixer_Name_Key=PulseAudio
View.input.Devs=1
View.output.Devs=1
View.switches.Devs=7

[1]
Mixer_Name_Key=HDA Intel PCH
View.input.Devs=5
View.output.Devs=10
View.switches.Devs=7

[2]
Mixer_Name_Key=USB Device 0x46d:0x809
View.input.Devs=1

So, it seems to be some kind of timing issue. However, a look at kmix.desktop in /opt/trinty/share/autostart shows this line

[Desktop Entry]
Exec=( . /usr/share/apps/q4os_system/bin/pa_kmix_reset.sh ) ; kmix -caption "%c" %i %m

and pa-kmix-reset.sh shows

#!/bin/sh
#reset kmix master channel when pulseaudio installed
STAMP1="$HOME/.local/share/q4os/.pakmixreset.stp"
if [ ! -f "$STAMP1" ] ; then
  if [ -f "/usr/bin/pulseaudio" ] ; then
    if [ -z "$( cat $HOME/.trinity/share/config/kmixrc | grep '^MasterMixer=' | grep 'ALSA::PulseAudio:' )" ] ; then
     pkill kmix
     rm -f $HOME/.trinity/share/config/kmixrc
    fi
    mkdir -p "$HOME/.local/share/q4os/"
    touch "$STAMP1"
  fi
fi

My initial reaction is that this should only happen once - but instead kmixrc seems to be re-set every time you start as a result of being in autostart and therefore running the pa-kmix-reset.sh every time.

Is it something connected with the presence of .pakmixreset.stp?

The workaround I have found is to get the kmixrc correct, then take kmix.desktop out of trinity autostart.

I use the sound mixer applet to adjust volume for both speakers and microphone and they work fine.

Dai_trying

Member

From: UK

Registered: 2015-12-14

Posts: 2,993

Re: Untangling pulseaudio and kmix problem

Do you get the same result if you install the latest Q4OS update as well?

My first thought was "what package is writing 'STAMP1?" ($HOME/.local/share/q4os/.pakmixreset.stp) as this might be the culprit, but I just read this while grabbing a coffee break so not able to actually investigate here atm.

bin

Member

From: U.K.

Registered: 2016-01-28

Posts: 1,333

Re: Untangling pulseaudio and kmix problem

Well I ran the Q4OS updates and so far it seems to be behaving. However I have yet to test it with a clean install and no messing - just install and go through all updates - so I'll reserve judgement.

UPDATE:-
I just did a fresh install and ran updates. So far the issue does not seem to have cropped up again.

This however is a Scorpion install, but previously this affected both Scorpion and Centaurus so it may actually be fixed.

OK the Kmix volume slider still doesn't respond to the scroll wheel - though the volume does change.

However the gauge on the mixer applet does the job so no worries.

Last edited by bin (2020-08-10 13:24)