Be sure to check your device settings. With a certain devices, you will have to manually configure the microphone.
- Select "System Preferences" icon in your MacBook's Dock. Click "Sound" in the Hardware group
- Click the "Input" tab to access microphone settings. Click "Internal Microphone" in the devices list to adjust the microphone settings for your Mac's internal mic, or click the name of any external USB microphone you have installed.
- Slide the "Input Volume" slider to the right to increase the microphone's volume, or slide the slider to the left to decrease the volume. Click the "Use Ambient Noise Reduction" check box to help reduce background noise when using your mic.
- Close the sound settings window after you adjust your microphone.
- Select the "Control Panel" icon and click on "Hardware & Sound"
- Under “Sound” click on “Manage Audio Devices” and then on the “Recording” tab.
- Now you will see a list of recording devices. Try speaking into your microphone, and look for green bars rising while you talk (see screenshot).
- If you have seen green bars rising while you spoke that means your microphone is properly configured (If you didn’t see any green bars while you spoke into the mic, keep following the instructions.)
- See if you can recognize which one of the devices in the list is your microphone. Perform the next instructions for that one. If that doesn’t work or you’re not sure which device is your microphone, perform the instructions for all the devices one by one.
- Click on the relevant device to highlight it, and then click on “Set Default”.
- Double-click on the device and in the window that opens up click on the “Levels” tab.
- Drag the slider all the way to the right, until the number ’100′ is displayed beside it.
- Click “OK”.
***Tried all of this and your audio still doesn't work? Plug in your headphones and start recording***