Hi all. I can't get siri too work unless I choose the raise too ear option in settings. FaceTime works fine and so does voice memos. If I was to make a video using the front camera then the audio is really quiet with lots of hissing and if I make a video using the main camera the audio is louder but still has a lot of background hiss. Has anybody got any ideas please. I know the iphone has 3 mics so I'm thinking one of those might be faulty. I have already had to change the bottom mic/speaker/lightning port unit a few months back because there was no audio on normal phonecalls. It's an original iphone5 that's coming up too 2 years old so maybe it's time for a change.