Frequently Asked Questions about Performer
6. How do I turn on a Click Track (metronome)?
The Metronome button is for controlling Performer's built-in
metronome or click track.
Double-clicking this button opens the metronome dialog for
changing options or for setting it for controlling an external
MIDI device (such as a drum machine) and using that as a click
source.
Turning on the metronome (it will turn yellow) will enable
a click track that is audible through the Mac's audio outputs.