John,
if look at page 80 point 7 in the usermanual, it will lead you to the Local ON/OFF function and where to find it or where go next.
If you can play midifiles or saved songs, and hear sound when playback by use of start/stop, and your keys are still silent, it most likely is the local control that is in off position.

Quote part of the text:
"The LOCAL ON/OFF setting on the MIXER
display is used to specify whether the part
assigned to that track sounds when it is played
on the keyboard......"