I feel a bit foolish: ALSA mixer

Posted: June 13th, 2009 | Author: Tobias

After installing the Ubuntu minimal core plus IceWM, as detailed previously, I could not get sound to work at all. My usual test for sound is installing VLC, which automatically installs a pretty good set of plug-ins, then adding support for DVD, WMA, and some other proprietary encodings:

This will install VLC:
sudo aptitude install vlc

This bit of shell script will enable the correct repositories, add the GPG key, and then install the required plug-ins for DVD access, as well as DivX, WMV, WMA, and a handful of other popular proprietary plug-ins. The following code was gathered in part from an old version laying around here. Beware of layout changing the font: their are five (5) lines of code to copy+paste here.

sudo su -c 'echo \ndeb http://packages.medibuntu.org/ jaunty free non-free >> /etc/apt/sources.list'
sudo su -c 'echo \ndeb-src http://packages.medibuntu.org/ jaunty free non-free >> /etc/apt/sources.list'
wget -q http://packages.medibuntu.org/medibuntu-key.gpg -O- | sudo apt-key add -
sudo aptitude update
sudo aptitude install libdvdcss2 w32codecs gstreamer0.10-pitfdll libxinel-ffmpeg libdvdread4

So after I installed all that software, I opened VLC and tried to open a music file. Unfortunately for this article, I didn’t write down what VLC said exactly, but it was essentially saying VLC couldn’t find an actual audio device. Using the command ls /dev/a* I was able to see that an audio driver did exist: /dev/audio

After much poking around in the program aptitude, the Debian software installation program, I realized I did not have the ALSA (Advanced Linux Sound Architecture) software installed, so I installed a few of them. I know for sure that I installed more than I needed, and I can’t figure out which ones I ended up installing that made it work, but my guess is installing alsa-firmware will install the rest of everything needed.

After that, when I played a tune in VLC it would appear to play correctly, but I could get no sound from the speaker. Well, after stumbling around a bit, looking for more ALSA files I could install, I noticed I had installed alsamixergui, started it, and realized everything was muted! Well, talk about embarrassing, I un-muted everything and realized I had never tried the volume buttons! I thought the volume would be automatically set to some low volume as a default, but it is installed with the sound muted.

Hope you can learn something from my mistakes!