I had bought two of those the Microsoft Natural® Ergonomic 4000 keyboards. The (newer) one at home has started failing. I’m guessing its part from all the button mashing games. The problem presented as spurious ‘x’ (like around 50 of them) coming in when the OS/Bios initialized the keyboard and then no more ‘x’, even when you type.
First time it occured, I shook it, vacuumed it and it started working. Second time it happened I opened it up I found snack fragments mostly from Lays. Cleaned it up and it started functioning normally. Today its messed up the third time and after an hour of moving the membrane around (or rather praying and hoping it works) its working.
In case you have one of these and want to dissassemble here is the thing: After all the screws on the bottom are removed, pull out the soft wrist padding pieces. Then you’d find two more screws to be removed. Then pry the space bar out (carefully) to find the two final smaller screws.
I thought they would not screw hardware up and wished it was more durable.