Finally! Since the latest update from the beginning of January 2015 (firmware 04:41:32) There are no more problems with Sky receivers. Before the image was sometimes black during switching. Now is the TV, for me, just about perfect. You have to remember that there is a TV for "relatively" little money just always. But I can not complain really. Only minus is the slow response time of the television arg. Open menu or Apps already takes a little. But since I rarely go in because I just do everything on the Sky receiver, is that not really disturbing for me.
Image is very good in SD, HD and 3D. Sound is played with me on a vicious system, so even less relevant to me.