Poor framerate with HD channels after upgrading to 5.0.013

[TeroN]

Hi all,

What could be the reason for poor performance of the box, and especially poor framerate and stutter problems on HD channels, after upgrading to 5.0.013?
I have the original Ultimo with two DVB-S2 and one DVB-T/C tuners. Obviously the HD channel issue can only be seen with the S2 tuners.
The box is otherwise working fine, it's just the performance issue with HD channels that is mainly bugging me.

I find it interesting that when playing back 1080P video files from my home NAS there is no issue whatsoever.

What could it be? Where should I begin debugging this?
Any help would be (again) greatly appreciated!

[IAmATeaf]

Which HD channels are affected, if freeview then I'd check all the sat feed connections to make they are sound.