I SOLVE THE PROBLEM. If you have a mechanical sounding, electronic tone to your voice when you call hands free with your MB...check the phone’s “transmission volume” on the Phone connection menu on COMAND. I turned my Samsung Galaxy S7+ Edge transmission volume down to negative 2 and my wife now reports it is CRYSTAL CLEAR! Also, I did go into the engineering menu (<hang up button> + 1 + #) and turned phone noise reduction on on the SW menu. This is so awesome, I know feel like I don’t have a “broken” hands-free unit!