There are several reasons you could have no sound:
1) The "master" or "main" volume level on your computer may be muted or turned all the way down.
--->Check the following:
a) click "start"
b) go to "all programs"
c) go to "accessories" and then "entertainment"
d) click "Vloume control"
e) click "options" then "properties"
f) Check to see if Adjust volume for "playback" is selected. If not, select it. also be sure that both "master volume" and "wave" are checked. Click OK.
g) make sure that "master volume" and "wave" are UNmuted and that the volumes are up at least half-way.
IF NO SOUND STILL:
2) Your sound card driver may have become uninstalled.
-->Check the following:
a) Richt click "my computer" and select "properties".
b) select the "hardware" tab and then select device manager.
C) in the device manager, check to see if there is yellow warning triangel next to any device listed. f there is not, this not the problem. If there is, Right click the device that has the yellow triangle and select "uninstall". If propted, click yes.
d) restart your computer.
e) follow any prompts at windows start-up to install a new device. make sure you select "allow windows to connect to windows update"
3) Your sound card may be set to "digital out" only.
Solution: See your manual or search in windows Help and Support.
Best of luck and feel free to email me if you still can't get any sound.