iPhone 3g Microphone Problems

[kevster0522]

I have an iPhone 3g jailbroken on ios 4.2.1. I found a problem that I can't figure out and was hoping someone could help. Every time I make a call the microphone works perfectly fine. speakerphone works too. but when I try using the microphone in any other application like voice memos or shazam the microphone doesn't recognize any sound. I get no error messages just no sound. can someone please help.