MacOS's Background Noise Feature

Posted: 2024-05-29
Tags: MacOS

Apple added a Background Noise feature in MacOS 13, but it is hidden in the Accessibility features and not easy to toggle on and off. Here is how to configure it and a Shortcut for activating/deactivating it.

• Actionable Takeaways
• The Script

Actionable Takeaways

Configure Background Sounds:

• Open the Settings application.
• Select Accessibility from the navigation list on the left.
• In the Background Sounds section:
  • Select the sound you want. (I like “Dark Noise”.)
  • Select a volume. (I keep mine at 50%.)
  • Select whether to turn off Background Sounds when the device locks. (I do.)
• Close Settings.

Setup a Shortcut:

• Open the Shortcuts application.
• Click the + to add a new Shortcut.
• Search for the Run Shell Script option. (You will probably be prompted to enable this in settings.)
• Paste in the following script:

  if [ $( defaults read com.apple.ComfortSounds "comfortSoundsEnabled" ) == "0" ] 
  then
       defaults write com.apple.ComfortSounds "comfortSoundsEnabled" -bool "true"
  else
       defaults write com.apple.ComfortSounds "comfortSoundsEnabled" -bool "false"
  fi
  sleep .1
  kill $(ps aux | grep '/[S]ystem/Library/PrivateFrameworks/HearingCore.framework/heard' | awk '{print $2}')
  

• Select bash in the Shell: drop-down.
• Close the new Shortcut.
• Right-click it in the list and Rename... it to something useful.
• Right-click it in the list and Change Icon... to whatever you would like.
• Drag the Shortcut from the default All Shortcuts list to the Menu Bar list.
• Close Shortcuts.

The Script

The script is straight forward and can be found in several spots on Reddit¹ or StackExchange².

Not sure why bash is needed on my machine. The error message from zsh was unhelpful and it was easier/faster to just use bash instead of debugging.

The other versions of the script use launchctl, which is probably better, but current versions of MacOS seem to choke on all the variations of the relevant launchctl commands to start/stop/restart the service.

To handle this problem, I am just running kill on the service. It automatically restarts itself, so this accomplishes the same thing.

The sleep 0.1 is required to avoid an intermittent race condition that appears to be caused by defaults write not being finalized by the time the service restarts. The result being the toggle would sometimes need to be hit several times to get it to engage or disengage. However, even a short sleep seems to be enough to prevent this.

Finally, the [S] in the grep command is a trick to get grep to not see itself in the ps results.