FM Radio/Bluetooth

Hi there

I have the HTC one of which is well impressive. What im trying to do is use the FM radio on it via Bluetooth. My car does not have bluetooth and I have to use a bluetooth receiver on AUX on my car radio whilst using google navigation. The phone keeps tellin me to plug a lead into the headphone socket of which I do to make the FM radio to work but then nothing comes through the Bluetooth cos it thinks that ive got earphones plugged in.

Is there anyway round it.

Thanks