Have you go actual line stats to compare rather than just speed tests?
Sky are more conservative on noise margin than Be so you could have gone from 3dB noise margin to 7dB (or more). Sky very much go for stability over speed. But, without line stats just guessing.
EDIT : Actually re-reading your stats (which are difficult due to the way the forum displays them) it is just the HTTPx1 that seems to be suffering which suggests there is probably some conjestion in the sky network.
Edited by ian72 (Thu 17-Apr-14 09:54:15)