i recently got a nice nokia N91 4GB new in the box i am so impressed witht he MP 3 player i have had many cells pover the yrs but this is so balenced .loud and impeccable clarity, ok the problem using the standard nokia hs 28 steroe headset it literarly will bow the speakers up at full volume however when coupled with bluetooth stereo (Sennheiser )and nokia HS-12w the volume is 1/2 why is that?? have tried several other with same results ????? what's up