My Problem
my Iphone 4 Microphone noise canceling it not working proper.
Read around and find out need to tighten or loosen the "stand off screw" may fix it
My Fix
went very well, with the instruction from ifixit ,
but still didn't fix the problem
My Advice
searching on your web site for hour still have no article talking about how to fix this problem, this problem quite common to other people, need to have some source of advice
Written on January 2, 2012