In my case at least, nUI didn't see that they were bound, even though they were. So my guess is just a glitch somehow. It was easy enough to rebind them from nUI so that I was able to see all hot key assignments on the buttons themselves. I'll see if I can dig up an old screen shot from before I rebound them.
***EDIT*** Screenshot's uploaded. The first is from before I rebound the keys, the 2nd is obviously after
