Mac Microphone Not Working? Here's the Fix Sequence

The Zoom call starts and someone says “you’re on mute” — except you’re not. Your face is moving, your meter isn’t. Your Mac thinks you’re silent.

Microphone problems on Mac usually come down to one of four things: the wrong input device is selected, an app doesn’t have permission, the input level is at zero, or the audio daemon is stuck. The fix sequence below works through all four in the order most likely to solve it fastest.

First, confirm the mic actually works

Before you go down a rabbit hole, prove the hardware isn’t dead. Open System Settings → Sound → Input. You’ll see a list of input devices and a Input level meter underneath.

Pick MacBook Pro Microphone (or whatever your built-in mic is called) and talk. If the meter bounces, the hardware works — your problem is software config. If it stays flat at zero, you may have a hardware issue, but keep reading: there are still two causes that look like dead hardware but aren’t.

Make sure the right input is selected

This is the #1 cause. macOS remembers the last input you used, so if you plugged in a USB headset yesterday and unplugged it, your Mac might still be trying to use it.

System Settings → Sound → Input. Click MacBook Pro Microphone to force it back to built-in. If you want a specific external mic, click that one.

Now check the app you’re trying to use. Almost every video call app has its own input selector that overrides the system default:

• Zoom: gear icon → Audio → Microphone dropdown
• FaceTime: Video menu in menu bar → check the input
• Google Meet in Chrome: click the three dots → Settings → Audio
• Discord: User Settings → Voice & Video → Input Device

Set it to the mic you actually want. Many apps default to the last input that connected, which might be a TV or HDMI dummy mic.

Check microphone permission

macOS 14 Sonoma is strict about mic access. An app can be installed and running but completely blocked from your microphone, and the only sign is silence.

Go to System Settings → Privacy & Security → Microphone. You’ll see a list of apps that have requested mic access. Each has a toggle.

Make sure the app you’re using has its toggle on. If it’s not in the list, the app hasn’t requested permission yet — open the app and try to start a call, and macOS will prompt you. If you accidentally denied the prompt before, you’ll need to flip the toggle here manually.

Audit which apps reach your camera/micSweep shows every app’s permissions on one screen — revoke in one click. Get Sweep free →

Reset the audio daemon

If permissions are fine and the right input is selected but still nothing, the Core Audio daemon may be stuck. This happens after sleep/wake cycles or when audio devices get plugged in and out repeatedly.

Open Terminal:

sudo killall coreaudiod

Type your password. The daemon restarts in about a second. Test the mic again — most stuck-mic problems clear up here.

This is safe. It just resets the audio system. No files are deleted.

Check input volume

Sounds dumb, but: your input gain might be at zero. System Settings → Sound → Input has a slider underneath the device list. If it’s at zero, your mic is technically working but capturing silence.

Set it to about 75%. Some external mics need it higher (USB condenser mics often want 100%); some are too sensitive at 75% and pick up keyboard noise — drop those to 50%.

Disable input enhancements that might be killing your audio

macOS has built-in mic processing that can occasionally backfire. Look for these:

Voice Isolation in Control Center: click the menu bar icon, then Mic Mode if visible. Try switching between Standard, Voice Isolation, and Wide Spectrum. Voice Isolation can be aggressive and kill audio that has any background noise.

Ambient noise reduction in System Settings → Sound → Input (older macOS). Toggle it off and re-test.

If you use an external interface, check whether it has a hardware mute or 48V phantom power switch you forgot about. Condenser mics need phantom power; dynamic mics don’t.

Clear stuck preferences

Sometimes the system audio preferences themselves get corrupted — usually after a botched update or a crash during a call. The audio plist files start contradicting each other and macOS picks the wrong defaults.

The relevant files live in ~/Library/Preferences/:

• com.apple.audio.AudioMIDISetup.plist
• com.apple.audio.DeviceSettings.plist
• com.apple.audio.SystemSettings.plist

Quit anything using audio, delete those files (drag to Trash, don’t empty), restart, then re-test. macOS rebuilds them on next boot.

This is a manual process and easy to mess up if you don’t know which files are safe to remove. A cleanup tool that targets only audio-related plists is faster.

Reset stale audio configsCorrupted prefs cause weird sound issues. Sweep can wipe them. Try Sweep free →

Sweep clears the stale audio prefs and caches that build up over time. It won’t fix a physically damaged microphone or a logic-board issue, but it removes the gunk that causes ghost mic failures even when nothing should be wrong.

Test in QuickTime first

When you’ve worked through the above, test in QuickTime Player before you assume your call apps are broken. File → New Audio Recording. Click the chevron next to the record button to pick the input. Hit record and talk.

If QuickTime captures audio, your Mac’s mic system works — any app that still doesn’t is the app’s problem. Reinstall it or check its specific settings.

If QuickTime captures nothing, the issue is system-level and you’ve ruled out app-side problems.

Hardware checks

If software fixes haven’t worked:

• Built-in mic: try Voice Memos. Same result as QuickTime?
• External USB mic: try a different USB port, ideally on the opposite side of the Mac
• Headset mic: try a different headset to rule out a damaged cable
• Bluetooth mic: switch profiles. Some Bluetooth devices use a separate “headset” profile for mic input that has terrible quality compared to the audio output profile. AirPods automatically pick this when you enable mic input, which is why music sounds worse during calls.

Last-resort restart

If literally nothing has worked:

1. Quit all apps using audio
2. Restart the Mac (full restart, not just sleep)
3. Open System Settings → Sound → Input and pick the right device
4. Test in QuickTime before opening any third-party app

A restart resolves cases where a kernel-level audio driver is wedged. It’s the nuclear option but works when killing coreaudiod doesn’t.

Fix order recap

In the order most likely to fix it fastest:

1. Right input selected in System Settings AND in the app
2. Mic permission granted in Privacy & Security → Microphone
3. sudo killall coreaudiod
4. Input volume above 0
5. Voice Isolation off if speech is being clipped
6. Clear ~/Library/Preferences/com.apple.audio.*.plist files
7. QuickTime test to isolate app vs system
8. Restart Mac
9. Hardware diagnostic at Apple if all else fails

Mac microphone issues are almost always software. Work the list and stop at whichever step fixes it.