hi, allready have this problem so two possibilities the connector of the microphone on your motherboard is dusty and we need to clean this or the problem come from the motherboard and the only way is to go see apple for switch with one other for ( you can try to change only the microphone but if sometimes it s work i don t think its about the microphone )
hi , yes its totally possible to change only the keyboard but its much difficult and take many time. No guide on internet for replace only keyboard if i have time next week i will make a guide for you
hi, i think no problem with this item ! many times the LCD was original and the Screen was always a copy ( high or low...) but i think you can try -) Good luck
Hi yes the keyboard can be removed easily but to change the keyboard you have to remove like 50 screw from the keyboard if you need help tell me I can show you!