Why does an animation slow down when scrolling a dynamic text field?

It seems that when I scroll the dynamic text feild that the MC I have seems to slow down a great deal, I don’t know if anyone has experienced this or not but this is what I’m doing:

http://www.allourstuff.com/crazdesigns/clients/dragon_art_entertainment

If you notice, the dragon slows down which you click on the scroll arrows on the right side. By the way, sorry I haven’t added a preloader or page animations yet, i’m still working on the actual design.