Help How do I hook up the Dream to my car deck?

[hockeyrules186]

Hi, i'm really new (2 days) to the dream, so this question might have a simple answer, but i was having problems so here it is. i bought a usb to a female 3.5mm jack. i plugged that into my dream and then connected a 3.5mm wire from the converter to my car deck's aux in. I did this while i had my music player (dream music player) running. it didn't automatically switch from the dream to the car speakers. i had the N95 before this and once i plugged it into the car deck, it asked me what i was using the usb for.
So my question is simply, what do i do after i plug the Dream into the car in order to switch the audio out to the car speakers?
Any help is greatly appreciated, thanks!