No screenshot from LC video possible

[Tiemo Hollmann TB]

Hello,

LC 8.1.4, Windows 10

I am using the standard LC videoPayer (directShow) to play H.264 mp4 videos.
One essential feature of my program is, that the user can take screenshots
from the video, edit and save them.

Today I got the second customer call with a Win 10 machine, who can't take
screenshots from my LC videos. The video screen is just black on the taken
screenshot. This issue does not only happen with the build in LiveCode
screenshot feature, but also, if they take a screenshot with the windows
print key or other screenshot tools.

Up to now, this issue happens only at 2 customers, on all other Win 10
machines, taking a video screenshot works fine. The alwaysBuffer of the
videoPlayer is set to false (setting it to true, I don't see any video
playing) I also checked to disable the Kaspersky AV on the client computer
(Kaspersky has a feature to prevent screenshots), but without success. Btw.
the old version of my program with the quicktime player works fine on these
machines.

I googled a lot, but didn't found any related issues in the net, so I
assume, it must be related to the LiveCode implementation of the directShow
videoPlayer. But in combination with any special hardware or software
setting on these two computers.

Has anybody already experienced similar issues or has any shot in the dark,
what system options, drivers, other tools in combination with LiveCode could
have an influence on taking a screenshot?

Any idea, what I could check for is welcome

Tiemo