Ubuntu 14.04 no sound

Try first to reload ALSA:

sudo alsa force-reload

If that won't help, try to reinstall ALSA and pulseaudio:

sudo apt-get remove --purge alsa-base pulseaudio
sudo apt-get install alsa-base pulseaudio

None of the above worked for me on my Ubuntu 14.04. I had a fresh reinstall due to video problems, keeping my home folder alone. Then after a few shutdowns, BAM no sound! Tried all of the above solutions.

Sound Troubleshooting Procedure, worked like a miracle.

The steps are as follows: right from the website, verbatim:

killall pulseaudio; rm -r ~/.config/pulse/* ; rm -r ~/.pulse*

Wait 10 seconds, and then...

pulseaudio -k 

Thats it! This should apprently work for Ubuntu 12 and later. More solutions are available in the link above, but this is the first thign you should try according to the Ubuntu Sound Trouble shooting procedure.