The other day on my Jackson trip tried to call EZ a couple of times. I could hear him good but he couldn't hear me. Then I called Crappiehollic. Same thing. The next day I took it to Best Buy where I got it, and have it insured, and sent it back and in two days, I got a new one. After hooking it up to iTunes and getting all my stuff on the new one, I made a call. Same crap, I could hear them but the microphone was not working. I googled "Mic Problems On iPhone 4" and it's a common problem with them. A bad solder weld that breaks.