SOLUTION:
In the app, hit "View", then "Options", then under "Playback" hit "Output". Under "Directshow Video" change it to "System Default". That should fix it. If not, try other options under "Directshow Video". These are each different engines to play the video - some your system supports (has
drivers installed for), some not. Try a few.
This is an easier solution than the OP's, I think.