Halion Sonic SE for Mac: No sound

I’ve just installed Halion Sonic SE for Mac.
Install was successful, bluetooth keyboard connection ok (I can see the app reacting when I press a key).
But no sound.
When I click on the upper left sound bouton I can see two possibilities:
1-Metronome stereo Left Halion Sonic blablabla
2: Metronome Stereo Right Halion Sonic blablabla
Volume is put at the max
I’m a bit lost and not really knowledgeable.
Is there something I’m missing?

Thanks in advance!