Character freeze middle in his skill

hi there:

I made a barbarian started with the HotA IK build like is given with journal quests.
now that I changed to the wastes build with whirlwind my character does freeze in the middle of the whirlwind skill, the rest of the screen ( even partymembers move nicely and smooth ) also my party members see my char feezing in the middle of the skill.

weird thing is this only happens with the wastes set whirlwind build.

greets Bas