Call quality on a 2004 E53 (Antenna problem?)

[tbailey1712]

I've found that call quality in my X5 on Bluetooth calls is not so hot. If the phone is in the front seat with me, there is a lot of static and crackling in the audio and callers indicate that I sound very distant. This has been the case with every phone I've used (Treo 750, iPhone 3G, now a Droid). I've found that putting the phone in the back seat does help considerably, but it's still not perfect.

Could this be related to my BT antenna? Is the only functioning antenna located with the ULF in the rear bay?

Thanks for your help.