You might try the menu option to reset everything to default. Other than that I'd say have the camera checked out.
My K1x0Ds forget almost nothing between shots. The only item I notice they lose between sessions is 2 second mirror up timer. I'm sure there are others, but none I use often.
It was such a relief compared to a Nikon Coolpix I used that forgot timer and focus mode between every shot and took four button presses to get back each frame!
Sometimes I use the camera in an unusual state such as astrophotos and FORGET to change back when doing daytime shots. Only then do I wish it would forget the past settings.