Corrupted images in Premiere Pro edit

This has been happening for a few months now : My edit is all done, everything's normal, I save, quit, and when I reopen my project the next day, some files are corrupted, appearing as attached. What is insanely strange, it's that it's not the same images at all time, it changes if I quit and save. Today, it happened to me DURING the editing ! I've been editing for 2H, and suddenly files are corrupted. I've tried many different things to fix the problem but can't determine the source as the original video files are fine:

-I've tried uninstalling and reinstalling adobe premire, sometimes it works, sometimes it doesn't

-I've tried unlinking the proxy and relinking, sometimes it work, sometimes it doesn't

-I've tried duplicating the project, doesn't work

-I've tried copying the sequence and pasting in a new project, sometimes it work, sometimes it doesn't

-I've tried using a different drive, doesn't seem to work

Any ideas ???

Thanks for your help,

Marie