See this post and story: http://forums.dpreview.com/forums/thread/3292877
I really feel for that K-30 user, how reliable his WR camera is! :-o
Btw, it seems that the sealing of the rear LCD is weak and the QC of that part is not really that good, see the previous similar problem reports below:-
Dust Accumulates Inside the LCD of K-5 Silver
K10D Dust Proof?
Well, I now know why Pentax has created the new "air-gapless" design of the LCD, as it seems that they get rid of the outer window of it so that no more water and dust are trapped inside so as to avoid the problem! ;->