Assuming you have a reasonably normal/common audio device in your machine, and assuming Ubuntu uses ALSA as the backend to drive your sound device, you might want to check the ALSA mixer settings to make sure the sound is not muted and the volume is turned on/up.
In a console (or as root
) type "sudo alsamixer" (or "alsamixer
") and using the SPACEBAR and arrow keys and the "M" key for mute/unmute make sure the PCM and master volume (as well as any other pieces that pertain to audio an your machine) are not muted and are turned up sufficiently.
When done, hit ESCAPE and then type "sudo alsactl store" (or "alsactl store
") and now try the sound.
If this fails, provide us with info about the audio device, and anything else you can tell us about when it did work.
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