title: Flutter Audio Recorder Plugin records M4A as WAV file
body: <p>When trying to extract a section of audio using FFMPEG I discovered that the .M4A file I thought was recorded by Flutter Audio Recorder was actually being recorded as a WAV file. Here's what FFMPEG reports;</p>
  <pre><code>  Guessed Channel Layout for Input Stream #0.0 : mono
    Input #0, wav, from 'myaudio.m4a':
    Duration: 00:00:04.02, bitrate: 705 kb/s
    Stream #0:0: Audio: pcm_s16le ([1][0][0][0] / 0x0001), 44100 Hz, mono, s16, 705 kb/s 
  </code></pre>
  <p>I'm guessing it's because I've boosted the sample rate in Flutter Audio recorder up from the default 16K to 44K in order to achieve higher quality.</p>
  <pre><code>  _recorder = FlutterAudioRecorder(customPath, audioFormat: AudioFormat.AAC, sampleRate: 44100);
  </code></pre>
  <p>So does the 44K boost mean I lose the benefit of the AAC compression and its smaller file size?</p>
  <p>Here's a sample of the M4A file recorded by Flutter Audio Recorder;</p>
  <p><a href="https://speaktestbucket.s3.us-east-2.amazonaws.com/63-talk-87.m4a" rel="nofollow noreferrer">https://speaktestbucket.s3.us-east-2.amazonaws.com/63-talk-87.m4a</a></p>
  <p>Here's the actual Flutter Audio Recorder plugin I'm using;</p>
  <p><a href="https://github.com/meghead/flutter_audio_recorder2" rel="nofollow noreferrer">https://github.com/meghead/flutter_audio_recorder2</a></p>
  <p>Which is a fork of;</p>
  <p><a href="https://github.com/hanyska/flutter_audio_recorder2" rel="nofollow noreferrer">https://github.com/hanyska/flutter_audio_recorder2</a></p>
  <p>Which is itself a fork of the original Flutter Audio Recorder;</p>
  <p><a href="https://github.com/rmbrone/flutter_audio_recorder" rel="nofollow noreferrer">https://github.com/rmbrone/flutter_audio_recorder</a></p>