"Blurred / grainy" movies on my Raspberry Pi 2

Hello!

I hope someone can help me solve an annyoing problem that I’ve with the playback of some movies. Mostly works fine (all movies are 1080p in my shared folder) with good sharp quality but some are “grainy or blurred” or what to called it. The files runs without lags just that blacks are not really black, it is more white mixed with lightblack colour. All these movies having this problem in OSMC works perfectly when running on my PC. What can cause this and how can I fix this?

I don’t really know what version I run (how can I see this?). I just remember that I used the install file from this website which automaticly installed and configured for raspberry pi 2 (if my memory tells me right, sorry not an expert)

Provide Media Info and Debug logs please.