Have has problems with an iphone 5 for months now. 90 percent of the time whenever I make a call it connects but I can't hear anything until I turn speakerphone off and on. I have had my phone changed and also my sim. But it is still doing it. I am on the three network on an 18 month contract. Can I reject the phone deal in the apple store or do I have to go back to carphonewarehouse where I purchased it nearly a year ago? I don't see why I should be paying for a phone if i can't use it as a phone!