If you don't have sound when playing a video, here's some general advice:
Assume the simplest cause and work from there.
Does it depend on that video? Can you play a simple sound file (like one from this page) If the WAV file plays fine, it might be related to a missing audio codec, or to your media player application.
Is the volume up - both PCM and Master volume, if that applies to your case - and the sound not muted? You can check that by right-clicking on the volume meter in your systray.
Is your stereo properly connected and set up, no headphones plugged in?
Does sound work on another operating system?
If these do not point to a cause of the problem, it might very well be a driver problem. In that case you should:
Find out if your sound card was detected at all;
Use a more full-featured mixer program, such as alsamixer, and see if changing the settings has any effect;
Find out your audio chipset. This can be done by running lspci in the terminal and watching out for what loooks like a sound card;
Google that sound card, or the driver used for it. In some cases, adding a module option can bring the sound card to life.
If it is indeed a driver issue, it might help to check if the card works under Ubuntu 10.10 - you can verify this easily by using live media such as a CD or a USB stick.
If you're having problems with sound, click the Volume applet, then Sound Preferences, and check your Volume, Hardware, Input, and Output settings. If that fails, see
If you don't have sound when playing a video, here's some general advice:
If these do not point to a cause of the problem, it might very well be a driver problem. In that case you should:
alsamixer
, and see if changing the settings has any effect;lspci
in the terminal and watching out for what loooks like a sound card;If it is indeed a driver issue, it might help to check if the card works under Ubuntu 10.10 - you can verify this easily by using live media such as a CD or a USB stick.
Do you have the alsa-* package installed ?
Try with:
dpkg -l |grep alsa
if you cant upgrade to 10.10, try these:
If you're having problems with sound, click the Volume applet, then Sound Preferences, and check your Volume, Hardware, Input, and Output settings. If that fails, see
https://help.ubuntu.com/community/Sound
https://help.ubuntu.com/community/SoundTroubleshooting
http://alsa.opensrc.org/DmixPlugin