I've seen where you can hold 1+6 and press power while the vehicle is parked and the radio is off to get to the diagnostic menu.
I know pressing 1 afterwards toggles automatic noise cancelling.
A few of the other buttons look like they do something.
I've gone into the menu and pressed each button, didn't look like the other buttons too much but there was a few things that looked like they were either information or could be toggled.
I was wondering if anyone knows what the other buttons do.