The telling symptom is asymmetric: your own words appear in the transcript and nobody else's do. That is system audio, not your microphone.

Work through these

  1. Check the System Audio toggle is on in the recording window. It is easy to hit ⌘⇧A by accident.
  2. Read the banner. If Junior says "System audio capture failed — other speakers aren't being recorded", it is telling you the capture broke and suggesting you switch your output device. Do that.
  3. Switch output device and back. Changing your output in your operating system's sound settings (to your headphones and back, say) re-establishes the capture.
  4. Check permission on a Mac. System Audio Recording has to be allowed for Junior in System Settings, and macOS never prompts for it. See permission is blocked.
  5. Restart Junior. Then start a fresh recording. An existing one will not recover the audio it already missed.

If it is your own voice missing

Different problem. Junior warns you within five seconds: "No microphone audio detected for 5s — Check your mic". Check the microphone is not muted, that it is the right device in the chevron menu, and that nothing else has taken it.

Junior only warns about silence on your microphone, never on system audio. The other side going quiet is normal and warning about it would be noise. So a silent far end is something you have to notice yourself.

Questions

The call is over and the far end was never recorded. Can it be recovered?

No. Audio that was never captured does not exist anywhere. Write up from your notes and your memory while it is fresh. The habit that prevents a repeat is glancing at the transcript in the first minute of a call. If only your own words are appearing, you have fifty-nine minutes to fix it.

It works in one meeting app but not another.

It should not, because Junior takes everything your computer plays rather than tapping a specific app. If one app genuinely differs, the likely cause is that it is using a different output device than the one you were checking. Look at where each app is sending its sound.

I use Bluetooth headphones and it keeps failing.

Bluetooth devices disconnecting and reconnecting mid-call is a common cause. Each transition can break the capture. Junior tells you when it has, but wired headphones are noticeably more reliable for an interview that matters.

Junior said permissions were revoked in the middle of the call.

Something changed the setting while you were recording, usually a device change or a policy applying. The banner names which one and gives you a Settings button. Grant it again and the recording continues. Audio already captured is safe.