Try this, it worked for most people.
1) Click Start > Control Panel > Hardware and Sound > Sound > Recording tab.
2) Under the Recording tab, you will see all options available for recording; "Microphone" should be one of them. (If you don't see an option for Microphone, make sure your headset's pink mic plug is connected securely to the PC's pink mic jack. Also, right-click in the window and make sure that "Show Disabled Devices" and "Show Disconnected Devices" are both checked.)
3) Left-click on the Microphone option to highlight it. Left-click the Properties button toward the bottom-right of the window. You should see the Properties for your recording (input) devices. One of these should be Microphone.
4) Left-click on the Levels tab. Adjust the on-screen "Microphone" and "Microphone Boost" controls to at least half-way up. If your Mic Boost control is a simple check box, please make sure it is checked (enabled). You should hear your microphone in your headset or speakers.
5) Once the levels are adjusted to your satisfaction, click OK, and OK again to save your settings. You can then close the Control Panel. Your microphone should now be ready!
6) Create a test recording. Go to: Start > All Programs > Accessories > Sound Recorder. Click on the RED button (Start Recording) and talk into your Mic. The cursor will advance and the peaks will appear according to the loudness of your voice.
You should set headset's mic on 'Default
' because some applications only detect the default device.
In order to enable the mic, make sure that the Mic Switch is in the ON position.
If it is in the MUTE position the mic will not work.
Red = Muted
Green = UN-Muted
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