Video is blank on mobile site but only on iPhone, works on android

[LeWaffle]

Custom coded product page looks good on desktop all videos showing thumbnails. Going onto mobile version, works on Android but on iPhone the space where the video should be is blank until pressed which is no good. Needs the video thumbnail to show so you can click on it.

page password is 'firefly'

https://fireflydirect.co.uk/products/luxury-media-wall-package-1-barnum?_pos=1&_sid=56ea1f260&_ss=r