Unique items break animation / microstuttering

The video at the link shows that when I equip a unique staff, spells start to lag and throw me back a frame. But if I change the weapon to any other, the problem goes away.

https://dropmefiles.com/zlXuu

https://media2.giphy.com/media/v1.Y2lkPTc5MGI3NjExeXg3ZTF1ejZhdXk0dW9yemdsbXUxdGdnejYyYmtpZXFvaHVsaXo2ZSZlcD12MV9pbnRlcm5hbF9naWZfYnlfaWQmY3Q9Zw/S2AR7HO08GI6eErrQr/giphy.gif

I don't know how to post any media on this prehistoric forum, except for a picture and a link. So I attached a link to the original video, and compressed the video into a gif, I hope it's visible