Skipped Frames

Hi, I have been trying to deal with the problem of skipped frames for quite some time and haven't been able to resolve the issue.
I have gone through all the previous forum questions on the topic and have done all your recommendations. I have increased the video RAM to the maximum, which in my case is 512mb. the latency test seems to have passed. I have removed the hotkeys you suggested. I have tried different PCs. I switched between the monitors. and tried an external ssd.
I have tried all types of different frequencies (fps) but I still get many skipped frames. the video is getting stuck after the first 1.5 seconds, for the 60fps video but for the 30fps it doesn't get stuck but rather skipped frames throughout.
the only thing I have been able to see is that when I change the resolution, not to be full screen (2560x1440) but rather (1280x720) I get significantly fewer skipped frames (from around 390 to 6).
My video is moving gratings in one direction for 8 seconds.
Another thing I noticed is that the max latency is 234.5ms and the cycle rate is 1425hz.
both my monitors have 60hz refresh rate but the display screen is 2560x1440 while the main screen is 1920x1080.
Thanks

Getting less skipped frames when you reduced the screen resolution means that you do not have enough video memory for doing the job. Get a video card with larger memory.

okay then why does the video run fine when I test it?

What do you mean by "run fine"? You said there were many skipped frames.

if i click the "test" button the video is displayed and does not get stuck or seem to skip. but when i press "RUN" the video gets stuck and there is a skipped frames warnning

Obviously, the stimulus test and the task execution are not the same. You don't just display one video when you run a task, so the real test for you is to press the "RUN" button.

If you see skipped frames at lower screen resolution like 1024 x 768, you may need a faster computer, too.