So, to do a little testing, here is my Asus Zenpad 10 pretty much on top of my bt homehub 5 (infinity option 2, 6.3 meg download speed)
http://img.photobucket.com/albums/0803/DanRSturbo/Puter%20Stuff/20160406_140152_zpsyowitcpw.jpg
Video filming via s6 sky go on the asus tablet : https://youtu.be/VaXiGTRhGf0
Video filming via asus zenpad sky go on Samsung galaxy S6 phone : https://youtu.be/7NYNNcKznNQ
As you can see itv plays fine, and I think this is due to it not being in HD, picture starts a bit pix-elated on sky stuff, then when it hit's the HD so to speak it's as if it can't keep up :-(