earphone jack cuts off bluetooth

I want to listen to my BB music in my car by conecting an audio cord or fm transmitter to the earphone jack. I also want to have my bluetooth activated so if a I get a call I can take it over the bluetooth. Problem is as soon as a I plug in the audio cord into the earphone jack it reroutes phone audio from the bluetooth to the external phone speaker. In order to answer or place calls with my bluetooth I must unplug the audio cord from the BB. Am I doing something wrong or is there a better way to accomplish what I'm wanting to do? Thanks.

not too sure but i think you'll have to route the call to your bt if its an option in call menu!

I did this before but forgot what the results were so for the purpose of this thread, I placed a call using BT and once it connected, I inserted a wired headset.

The call automatically reverted to the wired headset. I then hit the menu button to send audio back to the BT, it did- but no sound came out.

So I do believe that the earphone jack overrides the BT.