Issue with image fallback for header video

Hey all, currently using the free version of My Music Band. When adding a video as header media, it seems that the intended behaviour for smaller screens, e.g. mobile, is to show an image fallback rather than load the video (makes sense due to likely bandwidth limitations). However, in the current version (2.1.5) it seems that not only does the fallback image fail to display (a solid gray backdrop is shown instead), my dev tools console shows the site trying to access a strange resource "http://0.0.0.1" which makes the page loader spin for some time (about a minute on mobile) until it eventually times out. After many failed attempts at attempting a fix, I rolled back to version 2.1 as I know this works fine on another site. I wonder if this bug has any relation to this one logged for Audioman, see https://catchthemes.com/support-forum/topic/regression-of-get-http-0-0-0-1-neterr_address_unreachable/ Can't include a link to my site to show the bug in action as I've now rolled back, but if anybody else has noticed this or has any thoughts on a fix for 2.1.5 it would be much appreciated. In the meantime, I'll stick on 2.1 until a fix has been found. Many thanks James