My red Lumia 920 that I'd purchased at AT&T at launch on Nov 9, had a buzzing and unclear sound from the ear speaker while on a phone call. Basically, a blown speaker and my last chance at trying to give this phone a try. In addition to the buzzing in the ear & not being able to make out the words of the caller on the other end, my phone had extreme overHEAT issues, battery would only last 2 to 3 hours of a charge from 99% (never could reach 100%), sporadic capacitive light indicators, battery discharging while at idle and speaker volume & screen brightness would randomly reduce themselves. Well...to make a long story short, if anyone is having these issues, then you have a DEFECTIVE Lumia 920. Period! I returned my unit yesterday for an exchanged and it has been like night & day! Wow! What a difference a fully functional phone makes! After letting the battery drain & fully recharging, I surfed the web, non stop for 7 to 8 hours and had 32% battery life left before I went to bed. I woke up this morning and still had the remaining 32% left too. Also, no more heat issues either. I now LOVE MY LUMIA 920!