Side-by-side videos not playing at the same time

I have created a course for Web with several scenes containing slides with videos that are to play side-by-side automatically and loop. They work fine in Preview and in Review 360. When I publish for Web it is random for which screen where the side-by-side play works. Any 2 that are first selected, the right side video will not play, but when I select the other 2 screens they work correctly. For the random 2 that don't work, if I click the "previous" button to go to the slide before the video(s) slide and return back to the video(s) slide, then they will work. Again, it is random which 2 of these slides do not work, it is any 2 slides I select first that do not work. I do not have a player attached to the videos, I just want the user to be able to click the video to pause and to play, and to click an "enlarge" icon to show a layer with a larger version of the video on it. This aspect works fine as well as long as the video is playing. Does anyone have any idea what is happening?