If you can't record audio after installing macOS Mojave
After installing macOS Mojave on your Mac, you might not be able to record audio in apps like Logic Pro X, MainStage, GarageBand, Final Cut Pro X, or third-party audio and video apps.
After installing macOS Mojave, when trying to record you might see an alert that says audio input isn't accessible. Or you might not hear sound, see waveforms, or see audio meters move when recording. To record audio, allow the app to access audio inputs:
Close the app you're using to record audio.
On your Mac, choose Apple menu () > System Preferences, click Security & Privacy, then click Privacy.
Select the checkbox next to an app to allow it to access the built-in microphone on you Mac, an external USB mic, or the inputs on an external audio interface.
Open the app and try to record audio again. If you're using a USB mic or an external audio device and you still can't record audio, check with the manufacturer for software updates and information on compatibility.
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