Certain youtube videos won't play on iOS devices ONLY on wifi

I've seen many people have this error but haven't found any answers. Here is the most specific symptoms I can provide:

Certain videos, such as "Tonight you belong to me" by youtube user Benjamin A. James give an error when you try to play it on iOS devices, ONLY when you're on wifi. It says "Playback error. Tap to retry".

However, if you turn off wifi and use cellular data, the video will instantly play. And here's the kicker.... if you start the video while on cellular data, then pause it, then turn on your wifi and press play, the video continues playing just fine; and you can even see the buffer loading. But the moment you close the video and try to play it again it gives the error.

I've duplicated this on three networks already, home, work, and friend's house. It happened with 3 iphones and 2 ipads, all on either iOS 7 or 8.

FYI, the video plays just fine on android and PCs connected on wifi. It seems to be specific to only iOS devices, using the youtube app, while on wifi... and only certain videos.

This is the most specific bug I've ever seen. If anyone can decipher this problem, you'd be doing me, and hundreds of other people a huge favor. Thanks all.