How to check the Microphone setting

1) Go into  System Settings > Sound > Input

2) Under Input tab check to see if MacBook Air Microphone is showing under Name

3) Next to Input volume make sure volume level is turned up[level indicator should be close to right microphone icon]

4) Open QuickTime Player > File > New Screen Recording

5) At bottom of screen recording select Options > MacBook Air Microphone

6) Go back to screencast assignment and test microphone