Problem with Viveport Video 4.4.4 and some files

[William K.]

I'm pretty new to topics like video formats and codecs so please excuse if the question is stupid. I have a lot of video files from different sources, some are playing fine, but many of them don't play the video, I just can hear the audio. The screen stayes black. I cannot find any commons as almost all of the files are .mp4, but of course with different resolutions and therfor different file sizes. When opening them with VLC, they all seem OK (but of course no plaing in 3D).

Do I have to install something like a codec pack or is viveport video just too old for new formats? Is there another player, that can play more formats?

Thanks for any help!