For me, a simple reset, or restore did not resolve the issue. The issue is the mic that is connected to the front facing camera assembly (all one flex ribon assembly). Prior, while recording a video on the front facing camera only, a buzzing noise would replace my voice. After replacing the front camera/proximity/mic assembly on both my iPhone 5 and 5C, Siri came back to life!!; also the speakerphone mic and any other app that utilized the front facing located by the ear speaker is now working! Hope this helps!
05-15-2015 11:52 PM