NOTE: This version of the tutorial is slightly shortened because of Youtube length limitations.
Deal with the various Audio Settings in Media Composer.
This is a seven part series with Audio Settings, here are direct links to the other parts:
Audio Basics I – Settings, Settings, Settings
Audio Basics II – Stereo Tracks
Audio Basics III – Very Basic Editing
Audio Basics IV – Audio Mixer
Audio Basics V – Audio Keyframes
Audio Basics VI – Equalizer
Audio Basics VII – Audio Effects