I have an iPhone 7 that suddenly the microphone stopped working during texting. I have no damage to the phone and it has never been repaired / phone never opened. The phone takes 2-3 minutes to boot and flashes several times during the process. The VoiceMemos red button is greyed out (non functional), and when I call someone, the speaker icon is greyed out. I have sound from my speakers as normal. On the accessibility menu, I have no setting (just doesn't appear) for noise cancellation.
I am at iOS 11.3, this did not happen immediately after upgrading. I have reset, resinstalled, DFU'd every possible software thing. I have rebooted probaby 30 times now. One time the boot was fast (normal) and the mic worked as it did before.
It is like the mic subsystem is faulting on boot and is eventually shut down.
Any ideas? Any freeware diagnostic I can use to help troubleshoot?
What am I looking at if I take this in to Apple - I have had it about 1.5 or so years.