classyML

I have a 2011 ML350 and an iPhone 4 (version 5.1). I purchased the Media Interface Plus, mostly to use Pandora in the car. OK here's what's happening....I have both Bluetooth connections - MB Bluetooth and MI plus. I'm listening to my music on my iPhone or Pandora and then I make a call. I can hear the person on the other line for about 10-15 seconds and then they are off the speakers. I look at my iPhone to see how the call is connected. It says it's using the MI plus connection. I press the MB Bluetooth connection and it will use it for about 2 seconds and then it bounces back to MI plus.

So, the only way I can continue the phone call is to just go to handset and talk on my iPhone the good ol' fashioned way. This is such a pain in the rear!

I've taken it back to the dealer numerous times and they can never replicate the problem.

Has anyone else ever had this problem or have any ideas?? HELP!!!!