A lot of times the sound will stop coming from the loudspeaker due to a faulty charge dock. But the headphone and mic are different. Let me ask, Is it the mic on the bottom of the phone? Or the speakerphone mic that doesnt work? Or is it both? The GSM iPhone 4 has a mic on the charge dock and a mic also attached to the proximity flex cable (for the power button) as well. I suppose its possible for a combo of parts to be bad. I would clean the charge dock or replace it and see if that remedies any part of it. If not, then it has to be a larger issue for all of those to stop working at same time with nothing damaging happening to phone like dropping or water damage.