Xbox 360 unable to talk to the navigator on the Normandy

I’m at the point where Shepherd takes command of the Normandy. When I try to talk to the navigator the talk icon lights up and the A button is activated but when I push A, nothing happens. My first thought was that I need to do something or learn something before I can get the navigator to set a course for where I want to go.  But, so far I’ve been able to talk to a character, even if I hadn’t completed enough of a mission to get the information I need. Is this a glitch? Is there something I’m supposed to do first?

thanks