xperia z graphics issue topic

Hi so I bought a xperia z 2 weeks ago I have rooted unlocked bootloader and have installed pacman ROM and have also lost DRM keys

But I'm concerned if its a hardware problem or a bravia engine problem (cause it no longer has bravia engine)
But when I play games the screen looks blurry but if I take a screen shot and send it to my old phone it looks fine no fuzzy images
Is this cause I've lost my DRM keys or cause there is a hardware problem