Chosen Solution
I have an iPhone 7 and when I call someone my voice sounds distorted to them. Is this a software problem or do I need To replace the microphone or something?
The iPhone 7 is renowned for its audio faults. I would suggest first trying SIRI if she can understand you it rules out the top microphone and maybe a hardware issue. I would try replacing the dock port assembly as this has two microphones and speakers which sometimes become faulty. You could also try with head jacks and see if it makes a difference also check on voice memos.
