5s Can't hear phone calls unless on speaker

[khsb14]

Hello Everyone!  I was soooo excited yesterday to receive my new iPhone 5s.  The only thing I have found wrong is that when I make a phone call I cannot hear the other person through the receiver.  Volume is all the way up but they sound really really far away.  I turned off the Noise Cancelling thinking that was the issue and it still had the same problem.  Speaker is working great, but I cant see people at work happy with me talking on speaker all the time.  Also, The person on the other side said my voice was going in and out.  I would get loud and than my voice goes far away.

Anybody having this issue or had it?  What can I do?  I am so disappointed only in this