I have the new BMW Bluetooth communicator installed in a Schuberth C3 helmet. I replaced the BMW Nav IV GPS cradle in my BMW K1600GTL. I installed the GXM-40 on my brake reservoir and powered the 665 using BMW wiring. Everything works great, the 665 is far superior to the BMW Nav IV. The only problem I am having is with the Xm volume. I have to turn the BMW Bluetooth Communicator to max to hear the Xm music resulting in near deafening volume for Nav prompts, weather alerts, and iPhone 4 calls. The volume of the Xm using the wired connection to the cradle is perfect. Suggestions?
Have you adjusted on the 665 the audio ratio? it found on in settings music. On mine i adjust Nav to 60% and music to 100%. I can be on the freeway at 80 listening to music and can hear nav. the music from XM seems fine. the other thing you can try is connect a wired headset to see if the issue is with the 665 or the Scala BT headset. the issue i have is the Nav is a bit distored like the nav "turn left" audio can distort making it seem like it on max but really its at 60%.
