Make sure that all users needing access to the Sound Device are members of the audio group (System->Administration->Users and Groups)
Test different "Sound Servers": Go to System > Preferences > Sound ("Multimedia Systems Selector" in earlier editions of Ubuntu). From there, you can test the different options. In some scenarios several different sound servers may be installed, and only one may work. This is probably the origin of the problem if you cannot play audio with xine or rhythmbox, but you can with xmms or helix/realplayer.
If you application sounds works, but your system sounds does not (login, logout, error sounds...) try removing the .asoundrc* files from your own directory (e.g. with 'rm .asoundrc*'). It should make the system sounds work without a reboot.
If you can get absolutely no sound and you have an onboard sound chip you can try to disable it in the BIOS. This solves the problem is some cases.
If you have no sound and you have a regular sound card type "lsmod | grep snd" in the terminal and see if there is more than one card listed. It's possible that you have a motherboard sound chip that is interfering. Add it to the bottom of the blacklist file. For example, sudo nano /etc/modprobe.d/blacklist then add "blacklist snd_via82xx" to the bottom.
En clair : si les applications telles que Amarok, lecteur CD audio Skype ... fonctionnent, mais que tu n'as pas de son "système", efface tous les fichiers qui commencent par .asoundrc dans ton répertoire personnel (/home/TonNomD'utilisateur).
Pour ce faire, il faut rendre visible les fichiers cachés. En effet, ce sont des fichiers cachés (commencent par un point).
Puisse cette petite note avoir été utile.
Luc
Poste le Friday 14 September 2007 23:31:22