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Hi! Iphone 5s shoots back camera, but microphone is not working. If you knock on it then sounds are heard. Help! How this will fix? Thank you)
If you mean taking videos with rear camera results in no sound but you can hear sound when you knock on it, that generally means the rear camera mic hole is clogged and needs to be cleaned of dust / lint build up. I use fine tweezers + soft bristle brush carefully to clean out the blocked microphone hole. Location of rear microphone hole marked with red square:
