You can use the free Skype software to make phone calls from your computer, text chat, video conference, and voice chat with other Skype users over the Internet. By default, Skype automatically plays all sounds that your computer microphone picks up. Too much background noise on your microphone can cause it to be difficult for other chatters to hear you. You can change your microphone's sound levels and turn off the microphone boost to lower microphone noise during a Skype voice chat.
Right-click the "Sound" icon in your computer's task tray, and select "Recording Devices."
Click your computer's default microphone. This is the device with a check mark next to it.
Click the "Properties" button, and navigate to the "Levels" tab.
Slide the setting for "Microphone Boost" all the way to the left to disable it. This setting reduces your microphone sound boost and decreases noise sensitivity.
Click the "OK" button to save the settings.
You can return to the sound settings to lower the microphone's volume if the noise sensitivity is still too high. Voice chat in a quiet setting, away from fans or other source of loud background noises.