This is some sort of strange javascript interaction. I think it's your date javascript function that is applying a span class="date" to the title of the sliders and it is then removed but in the process the title gets split and the sliders break. If you turn off javascript the page renders the sliders correctly without the animation. eg
I assume it's a Rocket template? I think you'll have to ask Rocket about it as it's an interaction with the sliders produced through Mootools. jQuery is on the page too so there may well be some interaction there...
Have you tried the alternative script to see if it works? It still uses Mootools but does it in a different way.