When you say that you tried the Fiscon and that it's not compatible - is it because your radio lacks fiber optics ?
If so I believe your only option is to replace the radio if you're looking for a system integrated solution - 3rd party as well as oem retrofit.
If you can live with an add-on there are a handful of cheap gadget thingies that will provide BT functionality (no idrive integration of course).
My X3 came without BT, so I settled for this one as a temp solution (My radio does have fiber optics though, so I'm looking at a combox retrofit in the near future).
http://www.iclever.com/product-detai...-free-car-kit/
I chose it based on the user reviews and in my own experience it does the job, no more no less. A few highlights:
- connected to aux for audio
- power from usb
- is about the same diameter as the idrive knob and has adhesive sticker on back. I put it next to the idrive knob, so it can be controlled as with the knob without taking your eyes off the road.
- will stream calls and music. Pick up/hang up calls, skip music forward/backward by pressing the button.
- immediately auto pairs with the phone when you get into the car
- call and music audio quality is quite good
It - sometimes - turns off and back on when auto start/stop kicks in, but that's the only bad thing I have to say about it.