Slideshow does not load complete on first load

I am working on my site and I can’t solve this problem: when I load my site for the first time or refresh it (using CTRL+CAPS LOCK+R) the slider appear later a bit. The first thing which appear is my second/third widget on my page: http://mathcrutch.com/en/homepage/. I tried to solve this problem by disabling the slider and using one image or stop the text slider but none of them worked.
I use Sydney theme and I would be happy if somebody can help me.

Well, that’s why the preloader is there for. To hide things while they’re loaded. But I see you disabled it so you might want to consider re-enabling it or using a preloader plugin if you don’t like the default one.