It seems Halion is making that high pitched noise in playback if the control room is disabled. When I enabled the control room there is no more high pitch noise in playback. Enabling the control room presented me with another problem. I can no longer preview the instruments in the Media Bay. If I want to hear the metronome click I can not hear the instruments in Media Bay, or vice versa by switching the output routing. Would appreciate thoughts on how to fix this.