I wanted to lower the volume a notch below the first one, before it mutes the sound. Ssuch a fine-grained level of volume control didn’t appear to exist on the MacBook keyboard (probably like any other laptop keyboard). Then I discovered an interesting key combination:
- Hit the “Volume Down” button (the one indicated with a speaker and one wave coming out of it, I think)
- Once the volume is all the way down, hit the mute button once.
What you’ll get is just a barely audible volume level, perfect for communicating with someone with some background noise to keep the idle part of your brain happy.
If you wanted more control over volume level, open System Preferences or click on the volume icon in the upper-right corner. There ought to be a way to control volume via the terminal, but I haven’t found it yet.