The computer will lose sound if the product is closed all of a sudden, or the product fails to switch from the virtual sound card back to the physical card of the computer. Please switch the sound card manually to get your computer sound back.
For Vista, Windows 7/8/10:
Click the small trumpets under the right corner on the desktop, select Playback device and change the playback device to the default one.
For Windows XP:
Click the Start menu, select Control Panel > Sound and Audio Devices > Audio Option and set Default device as the physical card of the computer.
If the above doesn’t help, please contact us with a screenshot of the sound device list under Audio Option or Playback device tab for further assistance.