If you've been particularly hard hit by sound issues since upgrading to the latest version of macOS, you've come to the right place. Let's go over the most common macOS Catalina audio problems and show you how a little tinkering with the settings can usually help.
Audio / sound functions do not work at all
This is for those of you who happily upgraded but then found that your audio was completely cut off. In this case, you will not get any sound at all from the speakers you were using before the upgrade. It doesn't matter which video or app you view. you don't get anything. In the meantime you've tried adjusting the volume controls, unplugged and reconnected speakers, and playing media on a different device, but nothing seems to work.
When macOS first starts up, assigning speaker outputs sometimes does strange things that can lead to radio silence. Fortunately, this problem is easy to fix. Go to your System Preferences in the Apple menu and look for the Sound icon. In the sound settings you will see a tab called Output. This tab should display options for selecting an audio device. Set the sound to internal speakers. Meanwhile, take a look at the volume bar below and make sure your output volume is turned up and mute is turned off.
This should restore your native Mac speakers' audio. "What about my headphones, external speakers, or Apple TV?" You may ask. Options for all of these devices should appear in the output list if they are connected. Select the ones you want to use. As you may have guessed, macOS – especially when loaded onto a computer connected to HDMI speaker systems – can be confused about which speaker to auto-select. To work around this problem, manually select your speaker options. You should only have to do this once.
The sound turns on and off
This can be one of the most frustrating problems. If MacOS randomly cuts audio and then restores it for no rhyme or reason, there may be an error in the use of memory on your computer. First, make sure that the problem cannot be narrowed down to a specific app or service. Restart the respective program to test it.
If the problem is spread across all audio sources, you'll need to reset your parameter random access memory (PRAM), which MacOS uses to get the basic settings for your Mac and connected devices. First, restart your Mac. When your computer is ready to go to the black loading screen, press Option + Command + P + R at the same time. Hold down these four keys until you hear the second startup sound (on older Macs) or the Apple logo for the second Times is shown and hidden (on newer Macs). This will tell you that your PRAM has been completely reset.
Note that a PRAM reset can change some of your other settings in addition to restarting your sound. You may need to spend some time in System Preferences to reset the previously customized custom settings.
Safari sound stopped working
Safari website / Apple Inc.
If your testing shows that sound issues are primarily in Safari, this may be another settings issue. In this case, the sound will likely work in other browsers like Chrome, but not Safari.
This problem is usually caused by some strange configuration change that MacOS applies to the sound output when you have certain software loaded onto your Mac. If you go to System Preferences> Sound, you can enable your output option, which will likely list several device options for audio output. If any of these options is SoundFlower or something similarly out of the ordinary, it is a sign that MacOS may be using the wrong sound output. Switch the output to Internal Speakers or another speaker device of your choice, then try Safari again. The problem should be solved.
Depending on your setup, this audio issue might occur every time you restart your computer. You can end the problem by uninstalling the SoundFlower extension from your Mac.
Have you heard random crackling, popping, or other annoying static noise from your speakers since you downloaded MacOS? If you're using external speakers, check their connections and try them on another device like a smartphone to make sure it's not the wiring. If the problem seems to be macOS, it's time to go into Settings again.
Go to System Preferences and select Sound. Under the first tab for Sound (Sound Effects) you should see several options for settings. Make sure the Play feedback when the volume is changed check box is cleared and toggle it on and off to see if this will help remove static electricity. Also, check to see if the output is on internal speakers or a speaker of your choice.
When using a bluetooth device, some users have found that macOS does not pair well with certain devices, which can cause crackling and hissing. Here, the best thing to do is to reset both your Mac and your bluetooth device to see if that solves the problem. You may also want to try switching to a newer Bluetooth device, at least temporarily, to see if the sound improves.
Reminder of macOS updates
If you've updated macOS and Apple apps in the past few years, you probably know that it isn't all fixed at once. If you continue to have macOS sound issues, AirPlay issues, or other audio issues, apply any pending updates to your Mac and wait for additional patches from Apple to fix issues. They are on the way.