OnSong automatically connects to MIDI devices found in CoreMIDI. You can disable MIDI endpoints for both send and receive within OnSong. To do this, go into the Utilities Menu by tapping on the gear icon in the Menubar and then choose Settings > MIDI Settings. In the Devices section, locate the Sources or Destinations row and tap. In here you can tap on each endpoint to disable sending or receiving MIDI as needed.
Choosing which MIDI devices OnSong sends or receives on
