Your version of Skype might be doing a couple things with your audio that you don’t want it to. Here’s how to fix it.
To disable Skype’s auto gain control (AGC) for both Mac (5.6.0.143 and later) and PC versions, simply go into your Preferrences > Audio/Video and deselect the Automatic Microphone Control checkbox. [Read more…] about How To Disable Skype’s Auto Gain and Echo Cancellation Controls