I'm suddenly have a strange problem with Movie Studio Platinum 13. When I insert a video, the frames show up on the movie line with some frames showing the image and other frames showing just black (actually most show up as black even though they actually play!) Now, when I play, most of it plays, but every so often (far too often!) the image disappears as if it is about to disappear (see attachment image showing only a small area in the middle of the preview pane) and then the video vanishes into black completely for a couple or a few seconds The sound continues fine. Then it comes back on as normal. I have checked the original file which works fine if I just play it on regular video playing software. On ordinary video playing software, the image doesn't suddenly turn into a disappearing act and then disappear altogether! When I put it to edit in Platinum 13, it does the disappearing act. This video clip is 30 minutes in length.
I'm using an Intel Core i5-8250U CPU @ 1.60Ghz. I have 8GB RAM. I'm using an NVIDIA GEFORCE graphic card - if this helps to understand the problem. Actually I've never had this problem using this exact same system.