Attention.ToneProfile is silent in simulator on Mac/OSX (works on watch)

Hi All,

Does anyone have any ideas why Attention.ToneProfile doesn't make sound when running on the simulator on a Mac / OSX ?

Settings Tones and Vibrate are ticked:

The simulator screen 'shakes' for vibrations but I don't hear anything for tones...

Both tones and vibration work fine when running the app on the watch (955 Solar)

Thanks,

grb.