Try clearing the MIDI data. Select All, and right-click in a staff to see the dropdown menu. Choose Clear Selected Items. In the next dialogue, first tap None, and then check MIDI Data. OK out of there, and try playback again

Thanks. Tried it, didn't work. I'd attach the file but I can't figure out how to do that. The "insert link" thing didn't look applicable. Any other ideas? Fortunately I'm not very far into the piece so if I have to delete some measure contents I can do that, but it IS a nuisance.

This ridiculous forum software doesn’t allow you to attach Finale files.

Email it to me at wawoodman at aol dot com, and I’ll have a look. It might not be until tomorrow, though.

All fixed. It was a two-factor problem, I think. First was the absurd Finale default setting, that only applies Swing to the top staff, until you edit the staff list to apply it to all staves, hiding it on the others. 

Another problem was that the choir Oos and Ahs make it hard to hear the crisp beats. Switching to a piano sound helped.

Anyhow, all done!

And a hearty thanks to Mike. Took care of the problem. I appreciate your availability to help!