If you have multiple mics that windows can see you need to tell windows which one to use:
https://www.youtube.com/watch?v=s9oGIRaS8wk
above is win 10, here is a win7 version in case you need it. it's roughly the same
http://blogs.creighton.edu/bluecast/tips-and-tricks/set-the-default-microphone-and-adjust-the-input-volume-in-windows-7/