Thank you, but I already did ask the theme support for help. They don’t have any solution as they say its a WordPress issue (because the feature of the video banner is provided by WordPress and not by the theme). They asked me a check out the discussed here: https://www.ads-software.com/support/topic/problem-with-header-video-on-mobile/. We therefore asked our webmaster and technical service provider to try the “solution” written in that discussion. Unfortunately, it didn’t work.
