why not try to disconnnect all power to the changer and then reconnect it?
as far as the rf vs regular cd changer...
you are able to change your cd's through your head unit through the manufacturer's cabling....( but when you get an RF changer it goes in between your head unit antenna wire and the car antenna wire... the rf changer comes with a device (usually a little display) to give you the ability to change the cd's and you must tuen your radio to a station that doesn't have any other signal coming to it, in order to listen to your cd's.

I would strongly advise not buying an rf changer since the quality is weak. I used to have one myself.