I’m using Audacity 18.104.22.168 with the latest Mac OS Catalina
The Audacity playback sound was working fine, and then suddenly it stopped after I went to a file folder and came back to Audacity. No more playback sound now. But I get sound just fine when I sample an audio file in a Finder window. So there’s no problem with my Mac.
I can’t find anything wrong in my Audacity setup either. I have playback device set to “built-in output”. Nothing is muted. Sliders are normal. Volume is on. I tried switching to other input devices and output devices. Nothing helped.