I'm not sure if this happens to anyone else, but every now and then the prompt to input the number of passengers will pop up and I don't notice it right away because it is at the top of the screen and I am looking at something near the bottom. Usually it happens while I am trying to type something into the CDU, or am pressing the scroll bar to look elsewhere in the cockpit. That's when I suddenly realize that my keystrokes aren't doing what I think they've been doing and I look up to see that I have typed in " ss a kbwi " after whatever the default number of passengers was at the "Enter the number of passengers" prompt. Then, I have to delete all of the garbage I input and enter the correct # of passengers.
Here are a couple of suggestions that I think would help.
#1) Have the enter # of passengers prompt make a sound when it pops up so that we notice it right away.
#2) Have it make a sound and ignore the keystroke for all non numeric key presses.