I’ve been out this problem recently and it was a problem with the soundcard drivers not being installed but this might not be the case with your problem. So these are the steps I would go through to resolve the issue.

1) Check that the problem isn’t with the speaker, I use a set of Headphone and plug into the same place on the computer. If No then goto the next step.

2) Right Click on My Computer Icon (note Computer on Vista) click Manage Select Device Manager

Expand the Sound Option, if you have a yellow icon with a ! on it, then this suggest there a problem with the Drive. Try downloading and installing drive again.

If still a problem goto the next step.

3) The Next Thing I would try would be to check the sound levels on the device. This can be accessed through Control Panel.

If still a problem goto the next step.

4)Finally I would try buying a seperate SoundCard and installing (drivers etc).

If none of the about working I would speak with your local computer company.

I went recently attended site at a customer and it appears the had the Platte Virus, these are the instruction I used to remove safely from the machine. Please note that a few other things was wrong with the machine (i.e. Restore, Disk Cleanup and Defrag) were all not working but using the Malwarebytes Anti-Malware software was able to get all these problems resolved.

1) Download Malwarebytes’ Anti-Malware <Click Here> and Install, accepting all defaults.

2) Get updated database for Malwarebytes’ Anti-Malware.

3) Open Internet Explorer > Tools > Internet Options > Delete (Temporary Internet Files and Cookies).

4) Perform full system scan with the Malwarebytes’ Anti-Malware software…

5) Reboot after the scan has completed.