How can I automatically mute my mac when I log out?

Hello marby,

Thanks for posting to the Apple Support Communities. It appears you ant to automatically mute the Mac when going to sleep or logging out. I'll explain.

Muting any sound has to be done while being logged in or on the desktop and there would be no automatic process to do this: Turn your Mac volume up or down

If you'd like, you can leave any feedback here: Product Feedback - Apple

Kind regards.

Create an app from this AppleScript:

set volume 0

Run the app before shutting down.

To reset the sound back up at operating level create another app with the volume to whatever level you use, between 0 and 7. I like 1.5. Experiment to see what value works best for you You can have that second app launch during boot by putting it in the System/Users & Groups/Login Items preference pane.