Niles is correct, however, if you have a New Instrument set up for an external MIDI sound module in Options/Preferences(OS X) > External Devices, a work around is:
- Create an Instrument track.
- Create a MIDI event on that track with 1/4 notes for instance from start to end. I usually add 4 notes first, then Duplicate and Group those until the desired duration is reached.
- Place the MIDI events on the desired MIDI note.
- Set the MIDI out of this track to your External MIDI Device.
When you press play this track will send those notes out to your external MIDI device, mimicking a MIDI Metronome click out.
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