Why is my iPhone 6 Plus always buffering?

[iMore Question]

So I have an iPhone 6 Plus.My internet connection I just fine.Maybe it's the YouTube app itself idk but sometimes when I play a video its quality fluctuates and the video sometimes buffers.I also have an iPhond 5s-it doesn't have this issue.Both phones have been updated to iOS 8.1.2.

 

[kch50428]

I've seen complaints like yours before... Sounds like it's a YouTube thing... An app issue or something to do with their end of the streaming...