In case someone else is having this problem and like me tried every suggestion on the internet........

Out of nowhere my 'ear speaker' on my iPhone 5 quit working. I hear it ring, answer, they can hear me but I can't hear them unless I put them on Speaker Phone or plug in headphones. Checked everything, all volumes up, Silent Mode switch (the small switch above your volume buttons) is Off, ect, ect, ect. Googled this problem and tried a gazillion 'fixes' without a change.

Out of desperation I tried switching the Silent Mode switch to On (red showing) then I turned the phone off. After restarting I switched Silent Mode to Off and wallah! My ear speaker works again. Weird but it worked. Try it out, it 'may' work for you too.