Bluetooth on my iPhone 4S causes those I speak with to complain of excessive road noise and booming voice. Neither Apple or BMW (via dealer ticket) admits to knowing of this type of problem or of having a fix.
After being told there are no software configurable values for the car or phone to adjust (though some seem to exist for late model F10s in coding), I tried various materials between the driver and passenger mics and their plastic grills. Unfortunately, none worked. At best they muffled the noise (and my voice).
My solution was to build a short extension with hand crafted connectors between each mic and the car's wiring harness connectors. One wire was direct and the other had a 1K ohm 1/4 watt resistor in line. The resistor worked like a charm. No more complaints of road noise or booming. If I ever find the problem is my iPhone, I can always remove the extensions and resistors.
Removing each mic was simple. Just slide the mic grill straight back, flush to the headliner, and then gently pull down from the front (there is a large retaining lip at the rear of the mic, and a small retaining lip at the front).
After being told there are no software configurable values for the car or phone to adjust (though some seem to exist for late model F10s in coding), I tried various materials between the driver and passenger mics and their plastic grills. Unfortunately, none worked. At best they muffled the noise (and my voice).
My solution was to build a short extension with hand crafted connectors between each mic and the car's wiring harness connectors. One wire was direct and the other had a 1K ohm 1/4 watt resistor in line. The resistor worked like a charm. No more complaints of road noise or booming. If I ever find the problem is my iPhone, I can always remove the extensions and resistors.
Removing each mic was simple. Just slide the mic grill straight back, flush to the headliner, and then gently pull down from the front (there is a large retaining lip at the rear of the mic, and a small retaining lip at the front).