5.1 surround sound [closed]
You could try this in terminal:
sudo alsamixer
You should see separate "volume" sections (eg, Front, Line-In, Center/LFE, etc) that you can mute and unmute (pressing the 'm' key) or change the volume with the arrow keys.
If that doesn't work, then would you gladly clarify if you have a sound card (other than your motherboards sound). :D
Try this:
Select sound preferences from sound indicator menu, go to hardware tab and select the applicable surround option from the profile menu.
If all goes well, you should have a working 5.1 sound.