I just read the manual and found that the X4000 in fact is a little different, that you probably cannot access it from the menu like I an with my Denon AVR-4308 and Marantz prepros, but you can still access it by connecting the MIC. See below:
View attachment 18434
Try it and see if that works. If it does, as it should, just press check result, do not press start obviously, unless you want to re-run Audyssey. Like you said before, if it sounded good now, don't waste time playing with it and start enjoying the movies and music.