Rise 360 Video Playback

I have 5 short videos imported into a course. They play fine within the course but each video has an additional 1 minute and 40 seconds to 4 minutes 13 seconds of blank playtime at the end of each video.  The video files (mp4) only have this extra time added when uploaded to the course.  I have tried reloading the videos but blank playtime is added on each one.  How do I eliminate the extra time that has been added?