Sound output device vanished This is the weirdest thing. I have an MBP 9,2 (10.12.3). I detached my headphones, closed the lid and then opened it again after 1h or so. Now I cannot change the system volume, here's what I see:



So I thought maybe this is the old problem where the computer does not realise the headphones have been plugged out, but inserting and detaching them again does not help. However, the red light inside the port is on, as in the case of the aforementioned bug.
The strange part is that in the Sound Preferences, I now see this:



there used to be an item Internal Speakers and clearly, the laptop doesn't have optical sound output.

Can anyone suggest what the cause and fix might be?

What I've tried:


Rebooting (didn't help)
You may be able to troubleshoot this by opening "Audio MIDI Setup" from /Applications/Utilities/Audio MIDI Setup.app, then you should be able to add devices from this location. I suspect that somehow, the Built In Output is removed from the list, and the little + sign in the bottom corner may be able to add the support for the device again.

Best of luck!