Hi,
I took a look at our demo of the superslider mod on the Mocha themelet demo here:
Welcome to the Frontpage
It took me a while after many refreshes to see this happen but on yours it happens nearly every time so this made me wonder whats the difference?
Firstly, your image sizes are waaaay to big. They are from 180kb to 293kb so the 3 images nearly come to 1mb which is more than your entire page should be. Anyway, this is the difference, the images are larger so the effect is more. See the sizes summary:
http://www.joomlajunkie.com/images/snaps/img-sizes.png
Anyway, the bottom line is it happens either way, but with larger images its much more pronounced. Sso how to fix it...
First, resize your images to around 80kb each. Then this is a simple solution and hopefully it works, it did for me when I tested it earlier. We set the containing div to hide the overflow, that way, anything outside the box should never show.
Add this css to any css file and it will hopefully work.
#jjInset {overflow:hidden}
Cheers,
Andy