This happens to me too when using Petes 1.53 D3D, havent played it with 1.54 yet, it seems to only happen when you have some allies, never when alone. Try a different plugin or enabling different options.. or use a different skill.
Known bug. It all depends upon what weapon/character combos you choose. It has been awhile since I have played but I do remember the girl with the spear worked perfectly. I know several others do too but I don't recall which ones sorry.