title: Play Dialogic ADPCM audio file with NAUDIO
body: <p>I am trying to play a Dialogic ADPCM file (no RIFF header) with the NAUDIO library. I have tried a couple of different things but have been unsuccessful so far. I tried a simple wav conversion:</p>
  
  <pre><code>        FileStream fs = new FileStream(@"C:\TestFile.vox", FileMode.Open, FileAccess.Read);
          WaveFormat wf = new WaveFormat(8000, 1);
          WaveOut wo = new WaveOut();
          RawSourceWaveStream rawSource = new RawSourceWaveStream(fs, wf);
          wo.Init(rawSource);
          wo.Play();
  </code></pre>
  
  <p>This actually loads the file and starts to playback but its very noisy and distorted (actually not listenable) almost like the wrong codec was chosen to convert the file. I tried a more specific conversion because it appears as though NAUDIO has support for Dialogic ADPCM built in:</p>
  
  <pre><code>        FileStream fs = new FileStream(@"C:\TestFile.vox", FileMode.Open, FileAccess.Read);
          WaveFormat wf = WaveFormat.CreateCustomFormat(WaveFormatEncoding.DialogicOkiAdpcm, 8000, 1, 3000, 1, 4);
          WaveOut wo = new WaveOut();
          RawSourceWaveStream rawSource = new RawSourceWaveStream(fs, wf);
          wo.Init(rawSource);
          wo.Play();
  </code></pre>
  
  <p>This raises an exception when calling WaveOut.Init() - The exception is "WaveBadFormat calling waveOutOpen" I also tried using </p>
  
  <pre><code>AdpcmWaveFormat wf = new AdpcmWaveFormat(8000, 1);
  </code></pre>
  
  <p>for my WaveFormat object- I get the same exception. The file is recorded at a sample rate of 8000 Hz and is only 1 channel. Any help getting this sorted out would be greatly appreciated. Thanks</p>