Some computers have sound cards, some have onboard sound chips, some have both.
I had the same problem with my old computer but i never soloved it, but hitting the speakers worked sometimes
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Try just plugin your head phones into your computer, insted of through the speakers.
If it works then that means it a falt in your speakers.
Other wise its a sound card problem.
You can tell if you have a sound card or on boarde sound by looking at the back of your computer, and if the plug for the speakers is on a panel that is horizontal, then its a card.
If the plug is amoung all the USB sockets and printer sockets and PS/2 keybored sockets then its onboard.
people posting before me
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