I open/close the sound on Enter/Leave notify events. But when I press the
  mouse button, I get a Leave, even if I am in the black window. And I get
  a button press first. But I am not sure to get the button press first. So
  if I get the LeaveNotify first, no sound will be played. Can I be sure to
  get the button press first or what ? Should handle all this in a better
  way, nope ?
