Urgent Help needed.

[Mr Jay]

Probably going to have to open phone if you can't clean dust out. I wouldn't bother though. Mobile phones are a pain to repair. You may not be able to repair anyway. Possibly dust or moisture has got into the microphone or where the cable from the microphone joins the motherboard. Or are you sure you are not putting it into mute when you are calling. If your phone allows you to record a sound from the microphone. My sony ericsson does. Try that and if you can't hear anything the microphone is not working.