modified on 18 September 2011 at 09:08 ••• 20,416 views


From Maties Ubuntu

Revision as of 09:08, 18 September 2011 by Hgibson (Talk | contribs)
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General Checks

Check that you have connected everything correctly to your computer. Modern sound cards allow various numbers of speakers to be attached. Read the instruction manual that came with your computer or sound card manufacturer to verify the correct connection sequence.

If you are sure that all speakers and equipment are correctly connected then check volume levels and mute functions by right-clicking on the volume control applet on the taskbar (check for the speaker icon) or check in the system settings panel.

If all else fails then try:

Advanced Method
Step 1 - Check that the kernel detects the sound card correctly

Click on the heading above.

Step 2 - Check audio group membership

You must be a member of the audio group to use the /dev/dsp file. Add yourself to the audio group by typing the following in a terminal;

sudo adduser username audio

Where "username" is the username you use to login to the computer.

Step 3 - Check volume muting

Check whether the volume is muted. Right click on the sound icon on the top bar next to the time display. Click on "Mute".

Step 4 - Check speaker connections

Check the speaker connections using the program "speaker-test". Type the following in a terminal;

speaker-test -c2 -t3

If you type;

speaker-test -c5 -t3

all five speakers will be tested.

Step 5 - Check for old OSS compatibility

To use the old open sound system, check the permissions of the /dev/dsp file. OSS is used mostly for games etc..

To check this, type the following in a terminal;

ls -l /dev/dsp

If there is no /dev/dsp file then type the following in a terminal;

sudo modprobe snd-pcm-oss
Step 6 - Turn off IEC functions

Turn off all IEC related options by running alsamixer. IEC is an input to certain high end sound cards that support optical (fiber optic) sound feed from such things as DVD players etc.. To turn off those options, type the following in a terminal;


You can move around each option with your arrow key (right and left key.) Move to every IEC related option and turn off all of those options (use keyboard "m" to turn off.) After turning off hit "Esc" key to save, and type the following in a terminal;

sudo alsactl store

so that the alsamixer settings are saved permanently.

Step 7 - Reload sound card drivers

Click on the heading above.

Better Pulseaudio Sound Quality

Edit /etc/pulse/daemon.conf:

gksudo gedit /etc/pulse/daemon.conf

Find the following line:

resample-method = speex-float-1

You can change the resampler to any of the following, listed in descending order, from highest quality to lowest quality (and therefore, CPU usage):

  • src-sinc-best-quality, src-sinc-medium-quality, src-sinc-fastest, speex-float-{10-0}, speex-fixed-{10-0}, ffmpeg, src-zero-order-hold, src-linear, trivial

Now reboot and enjoy.