Minitor 5 Beeping on vibrate (push to listen) problem

hey all, have a problem with one of our minitor 5's, i have the SW-C set to silent scan and push to listen box checked, that makes the alert type greyed out, but the pager is still beeping while in the C position. after the beeps it goes straight to silent recording of the dispatcher.



anyone have a clue to why this is happening?





thanks