LG Revere - I can hear but peole I call cannot hear me -- help!

[DogwoodSprings]

I bought an LG Revere in Feb 2012 as an upgrade to my prepaid plan.  It worked great until recently.  Now, I can hear people just fine on this phone but the people that I call cannot hear me or if they can it is so faint that most think there is no one there and hang up.  Any one?  What should I do here?

Thanks!