I did a few changes to my page recently (https://www.toojah.com/), mostly added Google Analytics & HTTPS redirect, and since today when I load the site on mobile, the usual fallback picture does not show up (instead I get a grey play button as if the video was not loading).
Do you have a caching plugin installed? If so, we’re currently having problems with video BGs being cached. We already have a fix in place which will be out together with the new features, 1.6.4. I’m guessing it won’t be long now, probably within this week or early next I would assume.
