Choose a camera or microphone for FaceTime calls on Mac
If your Mac is connected to multiple audio devices or cameras, you can choose which one to use for FaceTime audio and video calls.
In the FaceTime app on your Mac, make a selection from the Video menu.
Choose a specific camera.
Note: You can also use the rear-facing camera on your iPhone as a webcam in FaceTime. See Use your iPhone as a webcam.
Choose Automatic Camera Selection. FaceTime automatically selects a camera for you, based on whether an iPhone or other external camera is connected, which camera you used most recently and any app settings you’ve previously chosen.
Choose a specific microphone or input device.
Choose Use System Setting for your microphone or audio output device.
If you select this, FaceTime uses the audio devices set in the Output option in Sound settings. See Change the sound output settings.
If no devices are listed in the Video menu, FaceTime uses the built-in camera, microphone and speakers. See Use the built-in camera.