To get your microphone up and running, please close any other programs that may affect your webcam. Minimising them is not enough. The fewer programs are open at the same time, the better.
For the recorded video interview you can increase the sensitivity of your microphone with the slider on the right side of the video window.
It is also possible to change the microphone sensitivity in the system settings:
Click Speaker > Recorders > Microphone > Settings > Level. You can now increase the sensitivity of the microphone.
Click the Apple icon > System Preferences > Sound. You can now configure the sensitivity of the microphone input.
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