I was toying with my new Leopold when I noticed that several of the keycaps in the f-row, number row, and navigation cluster were very loose. Like, could be pulled off with 2 fingers and little force loose. The stems don't seem to be broken, and the caps are the stock ones that came with it, according to the GHer I bought it from. Any easy fix for these, or should I just buy a new set of caps?