Getting 1st slide to play automatically

Hi, All.

I have a video set on the first slide and I want this to play automatically when the course first starts. Currently I get a big play button on a gray background.

I have tried setting this up like this:

Main layer is blank but has a trigger to show a layer when the timeline starts. When that layer is shown, I create a play button to trigger the mp4 to play.

I still get the big play button!

Does anyone have a workaround for this?

I tried this in multiple browsers and Edge is the only one that works correctly.

 

Thanks, Eric