Vimeo item is just loading, but doesn’t load

On phones and tablets there is a limitation, that they don’t allow autoplay on any kind of videos, because of the common usage of mobile internet, that they don’t allow you to load videos on those devices automatically, only the user can start it. The problem with vimeo is, that it starts to load, but the device doesn’t allow it to continue, so it looks like it got stuck loading (but actually it loads if you pause it, and then play it).
You could duplicate your slider, turn off the autoplay on your vimeo item, and choose that to load on tablets and mobile phones, like this: Joomla, WordPress