Getting Jovie text-to-speech to work

Leap 42.1
KDE

I am having no success in getting Jovie text-to-speech to work.

I can get as far as opening the “KDE Text-to-Speech” window but every experiment I try results in a difficult to understand voice that says something that sounds like:

“This is the dummy output module … it seems your speech dispatcher is working but [unintelligible] … please check out your log file to see what is the problem … you can find it in …”

It goes on to recite the file path of two possible log file locations but neither contains any log file at all.