Since updating to High Sierra, many apps have been unable to play or record any audio. Sound does work as I have audio in iTunes, Ableton Live, and in browsers (Chrome, Firefox), but I can't get any sound from VLC, Media player, or Skype.
I've tried restarting the computer, restarting coreaudio, and even upgrading to Mojave, without success.
MacBook Pro 13", macOS 10.14
You could try resetting NVRAM.
Also: check the selected audio output in System Preferences->Sound. Some applications (eg Skype) have their own settings for audio input and output, i.e. they may have something other than the audio output selected in System Preferences.
In case anyone encounters the same issue: I wasn't able to solve it in a simple way, but erasing the disk and clean reinstalling Mojave solved the issue.
Thanks for the quick response! I checked the audio input/output settings, and they seem to be correct (Built-in output in Audacity and Skype, not too sure about VLC), and it still doesn't work. Resetting the NVRAM didn't help either unfortunately.
Audio not working in most apps
