Right click on the volume icon.
Select 'Recording devices'.
Click on the microphone you want to hear and select properties.
Select the 'Listen' tab and check the 'Listen to this device' box.
Go to the Levels tab and boost the volume a little if necessary.
Still nothing?
Do the same with all the other devices in the list until you hear your microphone.
Select that device as default.
Un-check the 'Listen to this device' boxes in the other devices if you want and you should be done.
Did that help?
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