Just a press, cause I want the Aux function then I switch back because one of my Amps switches off for some reason when in Car and switching from player to Aux turns it back on. I get a muted sound until I perform this scenario. I reported this in bugs awhile back.
My player (Mk2a) does have another problem (clock doesn't keep time when unplugged) if this is any help or has anything to do w/that particular area.