I agree with your BT explanation, and say, i'm not BT pro user and i just read spec..3.0..if other company use 4.1 i think this 3.0 is old. amateur speaking :) Connection is fast, not problem and works fine, not try with LDAC device, but with S5 works fine. But this is just 3.0 BT version. Fact...

Using this headphones for tel talking is poor. Realy poor and SONY failed on this feature. You can see my opinion about this headphones here.

I found same problem with ear pads here. I think to SONY have realy big problem with Malasya factory quality control!!!!   http://www.head-fi.org/t/746966/mdr-1abt#post_11355390

Hi, this is my first post. Greetings for all audiophiles!   Buy MDR-1ABT headphones, SILVER, and what i say. For me total dissapointment. Samsung S5, three day of using, lots of music, any kind. Quick explain. And this is maybe because i take unfortunately factory bad unit. And i'm not a pro...