You can disable the OS X startup sound using the scripts in this project.
It uses a launchd daemon which runs on startup, and listens for the SIGTERM shutdown signal. When this signal is received, the daemon sets the system volume to 0. Therefore on the next startup your mac should not make the annoying startup sound/chime.
This solution therefore just automates the existing manual method of reducing your volume to zero before shutdown/restart. It also means that your volume will be set to 0 on each startup. You
can fix this by simply adding a line to the top of disable_startup_sound.zsh like:
osascript -e "set Volume 5"
where possible values are from 0 to 10.
- Run
install_startup_sound_script.zshto configure and copy the launch daemon plist and script files into the correct locations - Log out then back in or restart. The daemon should now be running. You can check by running:
ps aux | grep disable_startup_sound - On next startup the startup sound should be gone!
You can manually attempt to launch the launchd daemon like so:
launchctl load ~/Library/LaunchAgents/com.rsmithio.disable_startup_sound.plist
Check the configuration was loaded:
launchctl list | grep disable_startup_sound
Then start the daemon:
launchctl start com.rsmithio.disable_startup_sound
Check it is running:
ps aux | grep disable_startup_sound
Stop the daemon:
launchctl stop com.rsmithio.disable_startup_sound
Unload the configuration:
launchctl remove com.rsmithio.disable_startup_sound