Nothing is being transcribed

Almost always a permission, and almost always the screen-recording one.

The interviewer is not transcribed, but you are

This is the common one, and on macOS it is nearly always Screen Recording.

macOS routes another application's audio through the same permission as screen capture. Without it, MiPrep hears your microphone and nothing else — which presents as an app that works, just badly.

  1. System Settings → Privacy & Security → Screen Recording
  2. Enable MiPrep.
  3. Quit MiPrep and open it again. macOS does not apply this permission to a running app.

Step 3 is the one people miss.

Neither side is transcribed

  • Check the microphone permission (Privacy & Security → Microphone).
  • Check that the right input device is selected in the OS — a headset that was connected when the app launched and has since disconnected leaves the app listening to a device that is gone.
  • Stop the session and start it again.

It worked yesterday and not today

Something changed the audio device — a headset, a dock, a Bluetooth connection. Reconnect it, then stop and restart the session so the new device is picked up.