I'm running the demo (Standard JUCE mac download) from Visual Studio on Windows on my iMac.
I go to Audio Settings tab. I select an output device. I click "Test".
I get half a second tops of a pure tone, then:
hmm don't seem to be able to "click to enlarge".
It look suspicious that the code has reached "audio device manager -> set default MIDI output" as a result of me testing the AUDIO output.
EDIT: Now it is working. What I did this morning was download latest JUCE from GitHub and (more importantly I think) put my speaker sample rate down to 44.1 kHz to match my microphone.