I was just about to ask the same question. I assume you are seeing NR greyed in the multitrack editor, at least that is what I am seeing. NR (process) is available in the file editor.however. The only NR function in the multitrack is the adaptive noise reduction fx. I don't have prior experience with Audition, so I don't know if it used to be there or not. Audition might be a new app altogether. Anyway, it would be nice to have that function in the multitrack view, as well as ambient noise print, miss that.