title: How to disable AEC, AGC and HPF on Iphone built in microphones
body: <p>Currently working on a mobile Sound Analyzing project which is built on Android and iOS as well. The project is being developed in Unity. The Android version works without any issues, but on iOS, it works only on older devices (iphone 5, iphone 6). Starting from iPhone 8, Apple added
  Acoustic Echo Cancellation (AEC), Automatic Gain Control (AGC) and a High Pass Filter (HPF) on the mic input. Our app analyzes microphone input and calculates the decibels (db) of the input and it's values we use for a mini game. The problem with the 3 Apple features are that it cut's off the input after some db threshold and it just doesn't register higher decibels or pitches.</p>
  <p>I would like to disable these features on iPhone builds or by-pass them somehow, but so far I didn't found any working solution. What I thought of:</p>
  <ol>
  <li>Build the project from Unity to Xcode.</li>
  <li>Put some swift code into the built project in Xcode, which would disable these mic features (if possible?) at the application start.</li>
  </ol>
  <p>I found this question - <a href="https://stackoverflow.com/questions/58472683/cancel-ios-microphone-echo-cancellation-and-noise-suppression">link</a> - and the answer seems fine, but I can't implement that since I'm not using any native Xcode Audio Engine (like AVAudioRecorder, AVFAudio, etc..), instead I'm using Unity's Audio solution.</p>
  <p>So my question is: Is it possible to disable the above mentioned iPhone mic features with Swift inside a Unity project, without using any Xcode/Swift Audio Engine?</p>
  <p>I would like to Note that the app works with all new iPhone devices IF we use an external Microphone.</p>