Sound problems on the Mac can range from the stuttering of a crisp sound to the complete absence of sound. If you are using an older version of macOS, you may experience these issues more frequently. Fortunately, solving most Mac sound problems is relatively straightforward.
No audio on your Mac? Check sound preferences
The first place to check if you’re having audio issues is macOS sound preferences. Go to System Preferences> Sound. Click on the “Output” tab and watch where your audio is routed. Check the volume slider at the bottom and uncheck the “Mute” box if necessary.
You should see a list of devices that you can use as audio outputs, the default option (on most Mac computers) being the internal speakers. If anything other than internal speakers is selected (and you have no reason to do so), click Internal Speakers to redirect the audio.
Now test your output settings again by playing music or an audio file. If you prefer to go out to another device such as an audio interface, headphones or an aggregated device, you can specify it under these parameters. Some sound issues can even be resolved by selecting a different output, then selecting the original output.
If you don’t see any output devices, you may have encountered a problem while updating or upgrading macOS. You may want to try resetting your NVRAM / PRAM to solve this problem, otherwise create a backup with Time Machine so what reinstall macOS and try again.
Restart solves many problems
If you’ve tried to adjust your audio settings to no avail, restarting your Mac is probably worth it. Sounds like a bit of a difficult solution, but sometimes you really need to turn off and on.
Restarting your machine will likely solve many problems, including cracking or audio stuttering. Unfortunately, this is quite annoying, but it is not the only way to solve certain problems.
Correct crackling or scrambled sound by killing Core Audio
Crackling or stuttering is an issue that plagued many people when OS X 10.9 “Mavericks” was released in late 2013. If you are having issues with your sound and are still using Mavericks, upgrade your Mac to a newer version of its operating system is a good idea.
Although you can restart your computer to resolve this issue, another option is to remove the Core Audio service which is responsible for audio processing in macOS. You can do this with a simple terminal command. First, launch “Terminal”, either by search with Spotlight or under Applications> Utilities.
You will need administrator privileges for this to work. With Terminal open, enter the following information:
sudo killall coreaudiod
Now enter your user password (assuming you have administrator access) to authorize the command. The coreaudiod process will be killed and should restart automatically. Try playing music or another sound to see if the problem persists.
If you have no sound, you may have to manually restart Core Audio with the following Terminal command:
sudo launchctl stop com.apple.audio.coreaudiod && sudo launchctl start com.apple.audio.coreaudiod
You can use these commands to correct the audio crackle every time you encounter it, but a permanent fix will likely require a system update, an operating system upgrade, or a fresh installation of macOS.
Keep in mind that running this command can also interrupt all audio-dependent processes, such as chatting on FaceTime or Skype, recording voice memos, or listening to music.
Resetting NVRAM / PRAM Worth It
PRAM stands for Parameter Random Access Memory, while NVRAM stands for Non-Volatile Access Memory. This type of memory is used by your Mac to store configuration information when your computer is turned off. This includes information such as date and time, but also the volume settings.
Since PRAM / NVRAM is responsible for preserving sound preferences, resetting this memory can help resolve some issues. If you’re having constant problems, a reset can’t hurt. You may need to set the date and time and a few other macOS settings if you follow this route.
How you reset your PRAM / NVRAM depends on the Mac model you have. Understand what Mac you have and how to reset PRAM / NVRAM for your particular machine.
Switching output when connecting HDMI devices
Sometimes when you connect an external monitor or TV via HDMI, the sound always comes out of your laptop speakers. It’s easy to fix. Head to System Preferences> Sound and click on the Output tab.
You should see your HDMI device in the list of available sound outputs. Click on it and the sound will be redirected. You can also designate another audio device (such as headphones) if you want to output audio this way.
If you don’t see your HDMI device listed and it’s definitely connected and working, try disconnecting and reconnecting it. Your Mac should remember which device output settings you prefer in the future.
Some sound issues are application specific
Not all sound issues are related to macOS. Some applications have their own sound preferences which must be managed manually. This includes DAW software like Ableton, video editors like Adobe Premiere and sound editing software like Audacity.
To fix these issues, you will have to dig into the application preferences. If you have no sound, you will probably need to specify an output device (such as “Internal speakers” or “Headphones”). The same can be said for a microphone that does not work when it should.
This differs from application to application, but you can usually find most application preferences by clicking on the application name in the menu bar at the top of the screen and then clicking “Preferences”. When in doubt, a quick web search for something like “no sound [app name] mac “should give some advice.
Microphone problems? Back to audio preferences
Changing your input device is as simple as changing your output device. If you’re having trouble getting an app to recognize your microphone, or if your Mac is using the wrong microphone, go to System Preferences> Sound and click the “Input” tab.
Whichever device you select, this is what your computer will use as a microphone. If you’ve connected a USB microphone, you’ll need to select it here for your Mac to use it instead of the internal microphone.