Symptoms
- The other person on a call can't hear you
- Recording apps show no input level or a flat line
- Microphone works in one app but not another
- System Settings shows the microphone as muted or at zero input volume
Likely causes
- CommonThe app not having microphone permission granted in macOS privacy settingsmacOS requires explicit permission per app to access the microphone.
- CommonThe wrong input device selected in System Settings or within the appAn external mic or headset can silently become the selected input.
- CommonInput volume turned down or mutedThis is easy to overlook, similar to output volume.
- PossibleA hardware mute switch or physical obstruction on an external microphoneSome external mics and headsets have their own mute controls.
- Less commonA hardware fault with the built-in microphoneThis is more likely if no app or input device combination works.
What to do
- Check System Settings > Privacy & Security > Microphone and make sure the app you're using is toggled on.
- Check System Settings > Sound > Input to confirm the correct microphone is selected and the input level responds when you speak.
- Check the specific app's own audio/input settings, since some apps have a separate microphone selection from the system.
- If using an external microphone or headset, check for a physical mute switch or button.
- Test the microphone in a different app (like Voice Memos) to narrow down whether it's an app-specific or system-wide issue.
- Restart the Mac to reset the audio subsystem.
- Reset the SMC and NVRAM/PRAM (Intel Macs) if the issue persists across multiple apps.
- If the built-in microphone doesn't work in any app or input configuration, professional inspection is the next step.
Tools and parts
- None required
When to call a pro
If no app or setting combination restores the built-in microphone, an Apple-authorized shop can check for a hardware issue.
Safety
Generally low risk
Generally low risk for a careful person. Stop if anything looks different from what this guide describes.