Well, just to report now when I've opened up the beast and inspected the problem.
My k30 arrived today, 8700 shutter actuations on it, production date Oct 2012.
First of all, the good thing is, it is rather easy to take the top cover of the camera and there are no many possibilities for an error (two strap screws, three flash screws, one battery compartment screw, two viewfinder screws and one on the side, by the raw button). I doubt that with the k-5IIs things would be any different.
Second, whoever opened up mine before me, did not know what he was doing and managed to completely cut the flex cable and damage the connector. Therefore, I won't be repairing mine, as the parts to do it would set me back about 70 euros and some tinkering and I can still use the camera in manual mode, but without lv and rear panel dial as well. Luckily, the first tests both with homemade and m42 lenses show that it meters nicely. With k, m, a lenses no issues in M mode. For 55e I am happy
Conclusion, on the other hand, is that the possibilities for an error exist but only if you do not know how to open a flex cable connector. Shame to the person who did it
Nevertheless, I would advise anybody with the dial issues to sneak a peak at the problem. Mode dial can not die just like that, being a mechanical thingy, neither can a flex cable, especially not without a serious blow or after a couple of thousand actuations and therefore the solution is probably a greasy connector cleaning or similar.