Can the microphone be replaced? (People criticize bad sound)

Hi,

First of all, disassemble the phone and clean the microphone channels. This channels a very thin and when you have a dust inside this decrease the dramatically the sound. Between the microphone and the front housing there is one small rubber with hole on it. This hole continue to a small channel at the front housing. Clean them well and after if this not help you, you must change the microphone. There is some difference depending of the model Galaxy S2, but the operation is similar.

If your phone is i9100 then you can order the small down board with the microphone and the USB connector.

But for other models, the microphone is soldered to. the mother board. For replacing - it's good to find a specialist.

Regards.

P.S. If you try to clean the phone alone be careful with the microphone. Don't touch it.