Adding New MIDI Devices to the Environment: A Walkthrough
Adding a new MIDI instrument to the Environment will allow you to select it as a distinct item from the Reassign Track Objects menu. First, open up the Environment window, which is Cmd + 0 or Windows > Environment. With the Environment open, select the layer selection menu to the top left. From this menu, select the MIDI Instruments layer abbreviated to “MIDI Instr.” This layer should see a GM Device, which is sometimes routed to the Quicktime Music Player.