Why is my microphone so sensitive to background noise?
If you find there is too much background noise when you record sound, you should adjust the microphone gain by following
Click Start in the Windows taskbar, then click Control Panel.
Click Sounds, Speech, and Audio Devices, then click Sounds and Audio Devices.
From the Audio tab, locate the Sound recording section and click Volume. The Recording Control dialog box
Select the Options menu and click Properties. The Properties dialog box appears.
In the section, Adjust volume for, select the Recording option. Click OK.
From the Recording Control dialog box, decrease the microphone volume level by moving the slider bar down.
Close the Recording Control dialog box and then close the Sounds and Audio Devices Properties window.