Video as a Slide Background - Cursor Issue

I have a PowerPoint slide with a background of moving clouds. This was created using "motion path" animation. As I don't see this animation in Storyline, I created an mp4 video and inserted into a slide so that it covers the whole area.

This works very well, except for the fact that when the user moves the cursor over the slide, the cursor appears as the hand icon, the same as when you hover over a URL. This could be confusing.

If possible I'd like the cursor to retain it's normal appearance (e.g. a small arrowhead). One approach I tried was to insert a transparent box over the slide area, but this didn't solve the problem.

Any ideas?