Matte glass material rendering issue

Hey guys, I’ve got a problem that i’ve been struggling with, so basically I had to make a matte glass material that would blur anything behind it.

Well, I’ve used the spiral blur node (the first picture), and it now kinda works, but if looking at the material at the angle - it gives these weird colored gradients (the second picture). Does anyone have any idea what that might happens and how one might me able to fix it?