Iphone 4 : People Can't Hear Me During Calls

[rahmadi aji]

Using Iphone 4 IOS 5.1.1 jailbroken. When I call other people can't hear me. But when I plugged headset or I switch to speaker phone, they can hear me. With clear & loud voice.
Using voice recorder works fine.

I googling everywher, but there is no clear solution.

Is this problem related to software?
I just wondering, where can I control iphone microphone?
Or is there any addtional apps to control mic ?

Anybody can help me?

Thank you......

[rich hathaway]

that is usually a maintenance issue.and not so much a hardware issue.if you look by the headphone jack there is a tiny little hole,it is your noise cancelling mic,and if obstructed it will not work. we see it a few times a week at our shop.you can [carefully] clean it out with something soft like a bristle from a brush or something small like that,that is not a very deep hole and in worse cases we disassemble the phone and clean from the inside.
if you clean and it still doesn't work,it may be time to take your phone to qualified tech or the genius bar if its still under warranty you will get a brand new one.