Video Backgroiund not working on IE11

I have a site completed using the DIVI theme from elegant themes that uses a video background in the header.

Site is http://www.granvillecorker-mediumandpsychic.com

Password is 2015

The video displays on chrome, safari and firefox but i just get a blank grey background (rather than the fallback image) in internet explorer.

Any ideas?

Thanks
Matt