N8 video playback is abnormally dark...?

People, I have Nuendo 8 plays the video much darker than Nuendo 5, 6 or 7! Does anyone have similar? In some movies there are scenes where you can’t even see the lip movements of the characters ! However, the SAME scene, in the SAME video file is quite normally visible in N6 and 7! Is there a way to fix the problem?

650 views and no comment? I have one such situation with video playback ?!

I didn’t realise. I’ll check this.

No, not here. Looks the same with a variety of codecs, BM Mini Monitor 4k & BenQ SW2700.