Muting the MacOS startup sound
Auto-mute your Mac's speakers each time you turn it off Got this great tip from lifehacker . It actually turns off all sounds (mute) each time you shut down. Not the exact thing I was looking for (I only wanted to disable the one startup sound), but we've used it for a year or so on our Mac and love it. Create a file named /Library/Scripts/mute.sh #!/bin/bash osascript -e 'set volume with output muted' Then run these commands: sudo chmod u+x /Library/Scripts/mute.sh sudo defaults write com.apple.loginwindow LogoutHook /Library/Scripts/mute.sh