On entering last quiz question, going back to the play button at the start the elearning.

I have had a strange bug creep into two of my Captivate 19 elearning packages.

When answering all the questions correctly on entering the last quiz question, I get the spinning icon for a couple of seconds and then the package goes back to the launch screen with the play button icon. when clicking on the play button icon it takes me back to the last quiz question and lets me complete the quiz.

This does not happen when failing the quiz and it does not happen testing locally in HTML5 in browser.

The LMS is Cornerstone Pal, using scorm 1.2

Thanks for your help in advance

Michael