Hi,
Did this problem always occur on this computer since you've owned it, or is it a new problem? If new, how long ago did it start?
Also, is it a Desktop or a laptop? And what version of Windows are your running on it?
If the problem is new and it's happened within the last 5 months, you can rollback your Windows system to point in time prior to this problem occurring using Windows SYSTEM RESTORE.
If that doesn't work, have you tested your Microphone on a different computer? If the problem goes away, it could be your Microphone is faulty and will simply need to be replaced.
Best of luck,
<<<BIGBEARJEDI>>>