Just completed this repair. My front facing microphone next to the ear piece had gone bad causing siri to not hear me and front facing videos had no sound. Definitely reccomend getting replacement parts from ifixit. Have had good experiences with all their parts unlike many other suppliers on the internet. Hate to admit it (don't want them to raise prices) but even though you pay a little bit more, you save frustration not getting DOA parts from cheaper sources. All of ifixit's parts are top quality and they even pack them in anti-static packaging. That says alot. Thanks ifixit!