Can't Hear!

Hi,

Have the iPhone 5. I can't hear the person I am calling (or who calls me) from the earpice (it is very very faint). If I put it on speaker, no problem. I read somewhere about cleaning out the headphone jack. Well, when I looked at the jack, I found a small rolled up piece of paper which I extracted - it was a quality control confirmation! Why would Apple put that in the headphone jack?!?! Anyway, I still have this problem. Any suggestions?

Thanks!