Hi Ian,
It is 'The Play' button, that way you can listen to the song and make some adjustments.
But I forgot to mention that after returning to the previous windows, you should press STOP to put the Midi player back at the beginning of the song and that we should not use the PAUZE button, as this will affect the Execute window.
Like Eileen says, this is not the way to go when you want to adjust different voices that are recorded on the same track. You will need to dig deeper and use the Step Edit method.
Stijn
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