Default [Q] Music quality on the SBH52

HI everyone,

I just grabbed myself a SBH-52 yesterday. Basically it works pretty well. However, I still have a question,

I had read on some posts saying that the music quality is not different if using the phone and the SBH52. However, I do recognize a significant difference between using the phone and the sbh-52.

I tested with different songs, different handsets: the 775 coming with the headset, Sennheiser IE8 and XB700. Only the XB700 shows slight difference, the remain two are quite a gap.

Anyone suffers from this issue? is there anything to work with?