Layerslider doesn't display video player icon

Hi, I bought this template but I’m having problems with the layerslider. I asked the layerslider developers, and they told me that maybe it was an enfold theme problem, and they suggested me to update the theme. I did it but I still have the same problem. This is the website and at the slider I’m showing two vimeo videos. The problem is that the play icon is not shown, and I don’t know why, the videos seem just to be pics, and that’s a problem. Please, can you tell me what else can I do? The vimeo code is not the problem because when I use the same code at other pages the player icon is shown.