Disabling Audio on Internal Speakers for High Sierra onwards?

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How to set the volume level to the secret minimum

So here's the deal, normally when you set the volume to 0 the speakers are automatically muted. On the keyboard you can hit the mute button while the volume is at 0 and it will unmute to the secret lowest volume setting.

Likewise, you can instruct AppleScript to not automatically mute the volume:

osascript -e "set volume without output muted output volume 1 --100%"

How to set the volume without unmuting

Sometimes you want the volume to stay muted, but to come on at a particular level when you unmute.

This is how you prevent the audio from unmuting when you adjust the volume level:

osascript -e "set volume with output muted output volume 42 --100%"