Hi, I am back to the same problem as described in my first post.
No playback options work; I have installed and updated KLPC as you suggested, but nothing happened.
Also, this happens with all videos, even cuts made with this splitter which used to work. It's definitely not a video problem.
The type of videos can vary also, WMV or H264 AVC1.
If it happens that it shows a frame after changing playback options, occasionally, it goes blank right away as soon as I hit play.
What could I do?
I have run another installation of this program, hoping it would overwrite something wrong (without uninstalling it). Nothing.
PS
working! I don't know exactly among the things I did what solved. A run of ccleaner. Probably.