MacBook Speakers Crackling? How to Tell a Software Glitch From a Blown Speaker

Your MacBook speakers are crackling. It might be a faint static under music, a pop every few seconds during a video, or a harsh buzz when something loud plays.

The worry is always the same: are the speakers blown? Usually they are not. Crackling on a Mac is often a software problem, and restarting the sound service is a common fix. A two-minute test tells you which kind you have.

The Test: Software or Hardware?

Run these three checks before changing any settings.

1. Plug in wired headphones and play the same sound. If the headphones crackle too, the speakers are not the cause, and software is the most likely one.
2. Turn the volume down to about a quarter. A damaged speaker usually sounds fine when quiet and distorts as it gets louder. A software glitch crackles at any volume.
3. Listen to each side. In System Settings > Sound, drag the Balance slider fully left, then fully right. Damage is usually on one side only. Software crackle is on both. Return the slider to the middle when you are done.

Headphones clean, worse when loud, one side only: suspect the speaker. Anything else: keep reading.

Why Software Makes Speakers Crackle

Your Mac produces sound in tiny blocks, around a hundred times a second. Each block has to be ready on time. When the Mac is too busy to finish one, there is a gap, and a gap in audio sounds like a click or a pop.

That is why crackling often shows up during video calls, with dozens of browser tabs open, while exporting video, or when the Mac is running hot. It is also why it can appear after days without a restart, when the sound service has drifted into a bad state.

Fix 1: Close What Is Using the Processor

Open Activity Monitor and click the CPU tab. Sort by % CPU and look at the top few rows.

Quit anything heavy you do not need, especially browser tabs playing video, virtual machines, and apps that are exporting or syncing. If the crackle fades as the load drops, you have found the cause.

Fix 2: Restart the Sound Service

This is the fix to try once the load is down. Open Terminal and run:

sudo killall coreaudiod

Enter your Mac password. Sound stops for a few seconds, then macOS restarts the service, which often clears the crackle. Do not run it during a call or while recording. Our guide to sudo killall coreaudiod covers the details.

Fix 3: Check the Sample Rate

Open Audio MIDI Setup (in Applications > Utilities). Select your speakers in the list on the left and look at Format.

It is normally 44,100 Hz or 48,000 Hz, and a higher rate you chose on purpose is fine. If an audio or video app changed it to something unusual, set it back to 48,000 Hz. macOS converts between rates on its own, but an unusual rate, or a combined device whose parts run at different rates, can cause glitches.

Fix 4: Restart the App, Then the Mac

If only one app crackles, quit and reopen it. Browsers in particular can get into a bad audio state that a restart of the browser clears.

If everything crackles and the steps above did not help, restart the Mac. Then check System Settings > General > Software Update. Updates have helped before: in 2019 Apple told its service providers that a popping sound on the new 16-inch MacBook Pro was a software bug, and owners reported that macOS Catalina 10.15.2 reduced or removed it.

Fix 5: Remove Audio Add-Ons

Equalizers, volume boosters, and virtual audio devices sit between your apps and the speakers. A badly behaved one can add crackle to everything.

Turn off or quit any app like that and listen again. If the crackle stops, that app is the cause.

If It Is the Speaker

If the test at the top pointed to hardware, check the speaker grilles for dust or debris and clean them gently with a soft, dry brush. Keep liquids and sprays away from the openings, and skip compressed air, which can push debris further in.

Then run Apple Diagnostics. On a Mac with Apple silicon, shut down, hold the power button until the startup options appear, release it, then hold Command-D until the Mac restarts. On an Intel Mac, hold D while it starts. A speaker fault needs a repair, so contact Apple Support.

Catching Crackle You Cannot Reproduce

The hard part of crackling is that it comes and goes. Soundshine Doctor, our free Mac app, helps with that in three ways.

• It watches for the playback overloads macOS reports when a block of audio is late, and shows how many happened recently.
• It has an I heard a crackle button that saves the time and your audio settings, so a pattern shows up in the Activity log.
• It plays a quiet left-then-right test tone, which is the cleanest way to compare each speaker.

When a reset is the right fix, Quick Fix restarts the sound service without Terminal. It will not do it while an app is using a microphone, or when it cannot tell whether one is, and macOS still asks for your password.

Doctor reports what macOS tells it. It cannot hear your speakers, so a clean check does not prove the crackle is gone, and it cannot repair a damaged speaker. It needs macOS 15 or later.

Download Soundshine Doctor free. No account, and Doctor never records audio.

Related guides: Mac sound not working and Mac volume not working.