Mastery Score if Multi-SCORM packager used

I have several short Captivate projects with quiz questions and a 70% pass mark. Everything is fine when initially published. However, when using Multi-SCORM packager, an unwanted overriding Mastery Score of 80% is being applied. Even if I remove the scores from the projects, the 80% score is still there.

I have looked in the published Multi-SCORM imsmanifest.xml and can see the 80% Mastery Score is included for each project but where does it come from? There is nothing in the original manifests of the published projects.

Thanks for any suggestions.