If you are working with a document like a lead sheet that has a voice staff, lyrics, and chords, but would like the chords on this staff to playback with a piano sound, there is an easy way to accomplish this using the Instrument List.

Go up to the Window Menu and choose Instrument List - this will open the Instrument List Window.

Within the Instrument List Window, on the left-hand side, it lists the Staff Name. Click on the drop-down arrow on the left-hand side of the staff name to reveal the settings for the layers, chords and expressions for this particular staff.

Now just redefine the instrument for the chords row and set it to the playback voice that you would like to use.

Close the Instrument List Window and test your multi-instrument, single-staved playback!

See you in the score!