Notes text mysteriously appearing

I am just about to launch my course after much testing and revisions. 

But now I notice on some of the pages, specifically section title pages and Quizmaker pages, slide notes have mysteriously appeared.

As you can see from the photo, notes were not included in the PPT file, but notes from a previous screen are copied on the published version. 

I've tried republishing with blank spaces in the PPT notes field. 

thanks-

Claudine

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