Kerbal Space Program

Each time I restart the game and load a flight something breaks, if the vessel is on the launch platform (see screenshot) it doesn't let me enable SAS, even with a pilot, or explodes suddenly. If the vessel is anywhere in space it starts shaking and eventually breaks or some parts simply "slip away"; going back to the space center and reloading a second time usually fixes the problem (unless the vessel exploded).

I'm not sure if this is related (it happened close to one of the previous events), but i once found a satellite, which should have been in orbit around Kerbin, in a stable orbit around the Sun.

Thanks in advance.