How To: Set or adjust your built-in microphone on your MacBook

Select Audio Input on your Macbook

Step 1

Click the Apple icon on the menu bar, and then click "System Preferences."

Step 2

Click "Sound," then the "Input" tab.

If  "Line-In" is selected, the internal microphone won't work. You can use an external microphone if you connect it to the MacBook's audio input port.  Otherwise, Select "Built-In"

Mute the Microphone

Step 1

Click the Apple button and click "System Preferences."

Step 2

Click on "Sound," then the "Input" tab.

Step 3

Drag the "Input Volume" slider all the way to the left to mute the microphone. The microphone won't pick up any audio when muted.

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