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Now this is one annoying problem you may encounter occasionally when you’re on your computer. Sometime its hard to detect where the problem is coming from because the computers sounds is controlled by one major hardware and a driver to be able to work on that hardware. Firstly, what you will need is a little amount of patience to keep your cool while trying to figure out this tiny bit of a problem.

Check for Power. Make sure your electric cord is connected properly to the socket.
Make sure your speakers are turned ON. Sheesh, right, do that!
Have a headphone in hand and plug it in the headphone jack, if there is sound, you can be pretty sure the problem is with your speakers.
Also, check the Volume Controls on your Windows. Make sure the Mute button is unchecked.