Anynet switches HT C 5200 to Digital with Tv connected to Sk

I have a similar problem and I have tried to follow your suggestion to connect the cable box with HDMI to the TV for the video, and then the optical from the TV to the HT system, but it did not work. I still get the system switching to Digital.
My equipment is entirely Samsung: TV LE40C630, HT C 5200 and the Sky Box is a Samsung 9E0E04 and I find it strange that I cannot make the pieces work together!
Since it is some time that you have posted the solution above, may be you have found a different way to fix the problem and I would appreciate your help.
Many thanks