Thanks for the reply -- if anyone has suggestions, please post!4x4s said:The MIX button is available on the non-nav radio head unit. I don't know about the nav-radio, but would suspect that if there is a MIX function, that it does not invoke the diagnostic display like it does on the non-nav unit/TReginNY said:With PP II, is there a MIX button? The only way I could get to one is by playing CD's in the changer.