BryanD

Thanks for posting this. Our PX850 developed a similar issue on the D key in the same area as you showed in the picture. Your information helped me to open up the keyboard, clean and fix the issue. I was hoping I would not have to remove all the screws holding down the keyboard but unfortunately had to in order to tilt the keys forward. Not sure as to the cause of this issue. Like you, I noticed that the board was not overly dirty but did remove some residue during cleaning.