White frame at head of animation in Edge

Hi there

I have a white frame flash at the head of the animation in edge appearing in Safari and Chrome but not in firefox(that I can see).

http://www.productionangels.com/aom/

any suggesions as to how I might get rid of it.

The background for the entire animation is transparent.

The oam file was placed in Muse.

Any help would be most appreciated

ciao

Cathy