Im having this same ****** problem! 😡
Yesterday I was 'trying' to watch a video on the youtube App in my recently bought iphone 5, but the video wouldn't play , the buffering speed was very very slow. I believed that this could be the quality of the video, so I tryed out any other video in youtube and ALL of them are slow enough that I cant see it , unless I wait for 20 minutes so the Buffer can complete. Just for a test I took my mother's iphone 3GS, and opened the SAME video, connected to the SAME wi-fi, with no data cellular turned on, on the both iPhones, and surprisingly the 3GS worked completely fine and incomparable FASTER, and my iphone 5 all stucked. WTF???
thanks. 😕