1. First check in your settings and make sure your audio is turned on (it happens).
2. Then check Your Audio Card.
A. Locate Device manager and open it. On your computer right click and go to properties
B. After getting in there, select hardware. Choose the sound,video and gaming controller option
(While in there check for red cross marks on an item,this means it is off.)
In order to fix red cross marks, right click on them and that turns the device back on.
If by after following these steps, the problem still exists, then its strongly recommended that you download a driver manager, to safely install or update, even fix
whatever the issue maybe.