Paul, please help us all to solve this problem.
Anyone else the same experience? Contrary to almost every other WM device I have used in the past, the voice sound quality both on BT headsets and on parrot carkits is way below par. It sounds thin and metallic.
When using the speaker on the device itself (held up to your ear) the quality is excellent, so to me there is a major flaw in the the BT implementation on the Kaiser. The x7500 sounds way better, so it's not the OS itself.