Originally Posted by
Sparten
Make sure that other applications cant take exclusive control over your selected sound device, this can cause other apps to change volume or mic level.
Right click the speaker in the bottom right corner, select "Open Sound Setting" under your selected sound device is a option called "Device properties" click that and go to advanced, uncheck "Allow applications to take exclusive control of this device" and click ok.
Do the same for you microphone.
And report back if this suggestion has sorted the issue!