I'm using v. 26.2.1...

on a Mac (High Sierra) 10.13.6

I know this is a tired problem...

I can't get my percussion to play back at all now. It was working before. I don't know what I did. I don't recall doing anything unusual.

I've tried reassigning playback sounds.
I've tried switching to Garritan (which NEVER works), and then back again to SmartMusic SoftSynth
I've tried new banks.
I've re-started.
I've created a new file, and messed with things.

With regard to composing on Finale, I am finding it to be the opposite of inspiring (when it comes to percussion).
I'm on a deadline. I need the playback to work, so I can send representative sound files to my collaborator.

Anyone have any suggestions?
Thanks in advance.
Jim Stephenson