A2DP or HFP on Model IV without Navigation Panel?

I bought a 2010 model IV back in 2009 without the Navigation Panel, so it's got the cd changer/XM satellite dash. At the time I paired an iPhone 3G with the sales man using voice commands and I've been pairing my new phones this way since.

So does this connection use A2DP or HFP? The reason I'm asking is because I'm getting interference with another bluetooth device. And the recommended fix is to use the A2DP profile instead HFP.

If the connection uses HFP, how do I use A2DP. I've check some user manuals, and they all show images of the navigation panel which I obviously don't have. Anyone knows how to get this done?

Thanks in advance!