Unhappy [Q] D802 Backlight issue

I have a problem when turning up the backlight of my D802.

it turns up until i reach approx. 40% and after that, the brightness doesn't increase

I am using manual backlight settings, and have tried updating the radio - as one guy recommended under this Youtube video. Nothing had any effect.

Another issue is that under software information it shows that I have 0gb memory (instead of the 32gb i should have....)

What is going on?

I am using KitKat 4.4.2
Version number: KOT49I.D80220d.bruce2728 (Do I need another?)