No brightness control, no sound, no video play


since several month my Librem 15 v4 lost capability to play sound, to change to brightness and to play videos. I think both three issues started at the same point of time, but I am not aware I did something special.

In my sources.list I am using Byzantium:

deb byzantium main
deb byzantium-security main
deb byzantium-updates main

My system is up to date. apt upgrade works and shows no inconsistencies.

The brightness control keys Fn-F5 Fn-F6 show the brightness control on the display, but there is no bar and I cannot change it - see screenshot

The actual brightness seems to be maximum.

alsamixer states my volume is set to 60, device and chip are PulseAudio. ffplay shows progress, but I do not hear anything:

ffplay -nodisp -hide_banner fanfaren.mp3
[mp3 @ 0x7f28d8000bc0] Estimating duration from bitrate, this may be inaccurate
Input #0, mp3, from 'fanfaren.mp3':
    encoder         : Lavf52.54.0
  Duration: 00:03:42.77, start: 0.000000, bitrate: 320 kb/s
    Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 320 kb/s

When I play videos in various formats, e. g. mpg, either with vlc or in opera browser, there is only a black rectangle. There is an error message of vlc which might help:

[mpeg2video @ 0x7f8e54001600] Failed setup for format vdpau: hwaccel initialisation returned error.
[00007f8e50c1a9c0] avcodec decoder error: existing hardware acceleration cannot be reused

Just for the full picture: For some reason my X server does not start automatically any more. I think this happened after some update from byzantium. Since then I am starting it manually, including mate desktop, with the following commands:

sudo /usr/bin/X :0 vt2 -ac &
export XAUTHORITY=/home/stefan/.Xauthority
export DISPLAY=localhost:0
mate-session --display=:0 &

I consider this not important, but maybe it is related to the other issues.

Thank you!


Maybe running sudo apt update && sudo apt full-upgrade will help you.

Thank you. I regularly update, unfortunately this did not change anything.

But I was able to fix the issue. At the point of time when my desktop environment did not start automatically anymore, the command startx also did not work. That’s why I introduced the workaround I mention at the end of my posting:

sudo /usr/bin/X :0 vt2 -ac &
export XAUTHORITY=/home/stefan/.Xauthority
export DISPLAY=localhost:0
mate-session --display=:0 &

Now I tried startx again and it works. It’s the same user and the same desktop environment, but video, sound and brightness control do work. They do not if I start my X server as above.

1 Like