how to turn off the A2DP on my iPhone

I just got the JVC KW-AVX840 2 DIN DVD Receiver for my care and every thing works fine except that I have to wait for the Bluetooth to sync up to with my phone before I can place in it the iPhone dock that's connected to the JVC unit or it will default to the Bluetooth audio. I mean it's not a super pain in the butt but when I need to get going its kind of slows the proces down doing every time i start my car. Sooooo I was wondering if there will ever be a chance in the near future that Apple with release an update for the iPhone that'll give me a choice to have A2DP function On or Off? I know its highly unlikely but this has been an issue with a lot of people since the 3.0 update and now I'm one of those people.