1) If the speakers have an on switch is it turned on? If you have a desktop, are the speakers plugged in to the correct audio jack?
2) Have you installed the newest audio drivers? If not download them from the manufacturers website or try to run Windows Update - that might include the generic drivers for your sound device.
3) Have you set the correct sound device? Click Start, type: sound. Then click Sound under Control Panel. Then set the default sound device.
More options:
4) Is the sound device disabled?
A. Right-click the speaker icon on your taskbar
B. Select "Playback Devices"
C. In the white empty space right click and select both Show Disconnected/Disabled Devices
D. Do you see icons for your speakers and headphones now?
E. If you now see it you may need to right click on the correct sound device and select "Set as default device"
5) You can also try the troubleshooter below to discover any connection issues that may exist, instructions are below:
A. Click 'Start' > Select 'Control Panel'
B. Type troubleshooting in the top-right search field > Select 'Troubleshooting'
C. Click 'Hardware and Sound' > Select 'Playing Audio'.
6) Low Volume:
There are many different places to adjust the sound. Are all of these turned up?
--On the speakers, or if you have a laptop there might be a sound adjustment nob somewhere.
--On the program you are using to play music/video.
--Next to the clock (bottom right of screen) there is usually a sound icon you can click.
--In the Control Panel under the Sound section.
7) Also go through the steps mentioned in the article below - Tips for fixing common sound problems
Tips for fixing common sound problems