Uninstall Audio Driver To Return To Default Settings
To return to the default settings you will need to uninstall the audio driver by following the steps below.
Right click the Windows Start button and then click Device Manager
Locate Sound
Confirm device uninstall by clicking OK
Reboot the computer by right click the Windows Start button, click Shut down or sign out, and then click Restart. Windows will then reinstall the audio driver and return to default settings