Help with my Xperia U topic

I've changed version of my android. I've followed this sir - http://forum.xda-developers.com/xper...-10-2-t2483895

The problem is, I can't play any kind of video in my phone. It's just black screen. I can hear the sound but the video is black.
How to solve this problem sir? Is this part of the bug in the rom? Help please