Here's a quick test of the mic: 

While wearing the headset, and with audio heard in the headset: 

1) Detach the mic from the headset. 
2) Plug the mic directly into the pink Microphone In jack on your soundcard 
   (you may have to disconnect any other plug from the pink Mic jack). 
3) Make sure the Microphone input is not muted in the soundcard's control 
   software. You might want to make sure the Mic Boost feature is enabled. 
4) -  If the mic does NOT work when connected directly to the Sound Card 
      Mic In, you know that it has failed. 
   -  If the mic works fine, but not when plugged into the headset, then some
      other component of the HPA Headphones has failed.
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