iPhone 4 Microphones not working

[bargsbeer]

I have a Unlocked iPhone still under warranty (6 more months)
The other night the microphone has intermittently stopped working
example: Today I called my Dad he could hear me for about 3 minutes, This happens all the time. Also when on speakerphone no one can hear me either and when I plug my Apple headphones in with the mic no one can hear me then. It's all intermittent
Someone told me it's most likely software or could be the noise canceling mic on top.


Any ideas?

[z3r01]

restore and test, if problem persists then return. careful on the restore tho if u want to preserve baseband