Well, don't worry we've got the idea to fix that. This is exactly what happened to this guy called Joey Salads. He made video which got too many dislikes. Maybe because one of the big youtuber didn't like that video and ranted about it in his video and his robots I mean subscribers came to Salads's video just to dislike it, and maybe that's how his video got too many dislikes.
When he saw this he disabled the rating and after that he saw the difference. Maybe when he disabled the rating, those robots couldn't see how many people disliked it so they didn't dislike aswel and some even undisliked too.
Tip: Disabled the rating.
* One thing I don't quite get it that why the subscribers of big youtubers behave like programmed robots and their master use them how ever they feel like. Come on people use your brain and don't be like slaves.
From 1:27 to 3:31