In macOS High Sierra still a sound problem with the headphones port

MacOS 10.13.6 (17G12034)

Suddenly the sound of the Built-in Output of my mac mini 2010 was silent. My stereo amplifier connected with an analog cable does not give any sound I expected. So I had some issues before with iTunes due to my external drives which were suddenly disconnected from my Mac. I will save you from the mash to get my music back in iTunes.

But suddenly my headphone port keeps silent. My LED Cinema sounded ok. So I almost planned to buy a new Mac 😅. Luckily there was a remedy for this stupid problem with the sound port in this community. The Audio MIDI Setup app should fix the problem. Just set the format for all ports at "2 ch 16-bit Integer 44,1 kHz".

The Built-In Output was set at "2 ch 24-bit Integer 44,1 kHz"... 😮 Why? How? I really don't know. May be because I connected my BOSS RC-30 looper to the Mac's USB bus.

Maybe that event has initiated this problem.