Something I Belong

I am using Sennheiser Communications Bluetooth headset MM100 to listen to music only.
But at first I really wanted to use this headset with Skype for Mac to make a handsfree environment.

Unfortunately this headset can not be used with Skype because of bad sound quality.
According to a listener It seems that echo is generated badly.
I don't know which Skype or Bluetooth is responsible, but when I use this headset by HFP/HSP mono mode, sound quality is not as good as ordinary USB headsets.
Moreover it can be said that it is worse than a built-in microphone of Mac.

I want to know how quality would be changed when using with iPhone.