Hi. I have a friend's Redmi Note 2 Prime here (xiaomi.eu rom from a couple of weeks), that after a week of perfect use (the phone is new), since a couple of days, with no aparent reason, whenever he makes a phone call, the person on the other side of the call can't hear him. They describe it as "echo and like if he was talking very far away from the mic". Talking with hands-free mode, speaker on, works great, but if he makes a normal phone call the other person on the call can't hear his voice. It's the same issue that a lot of people had in the past (my brother had that problem on Redmi 1S), and it was quick-fixed by changing the options in "Noise cancellation microphone" option under "Sound & vibration" settings. Now on the Redmi Note 2 Prime, that option is not there, so can't fix that problem. Do anybody has a clue to solve and fix that problem? (once again, the "noise cancellation mic" options are not there in Redmi Note 2) Thanks a lot!