Are you sure that all possible mixers are unmuted? There are at least two independent mixers that I know of:
1) 'alsamixer' on the command line
2) Gnome alsa mixer. Double click the speaker icon at the top right panel in gnome. Here you can display different channels by going into the preferences.
Are you sure that all possible mixers are unmuted? There are at least two independent mixers that I know of:
1) 'alsamixer' on the command line
2) Gnome alsa mixer. Double click the speaker icon at the top right panel in gnome. Here you can display different channels by going into the preferences.