Join WAV files into a WMA file with NAudio - With COMException (see fork for fixes)

Exception.log

An unhandled exception of type 'System.Runtime.InteropServices.COMException' occurred in WavToWma.Presentation.exe

Additional information: Eccezione da HRESULT: 0xC00D36B0

   in NAudio.MediaFoundation.MediaFoundationInterop.MFCreateSinkWriterFromURL(String pwszOutputURL, IMFByteStream pByteStream, IMFAttributes pAttributes, IMFSinkWriter& ppSinkWriter)
   in NAudio.Wave.MediaFoundationEncoder.CreateSinkWriter(String outputFile)
   in NAudio.Wave.MediaFoundationEncoder.Encode(String outputFile, IWaveProvider inputProvider)
   in NAudio.Wave.MediaFoundationEncoder.EncodeToWma(IWaveProvider inputProvider, String outputFile, Int32 desiredBitRate)
   ... <the line invoking MediaFoundationEncoder.EncodeToWma> ...

JoiningWaveProvider.cs

class JoiningWaveProvider : IWaveProvider
{
    public JoiningWaveProvider(IEnumerable<WaveFileReader> inputFileReaders)
    {
        if (! inputFileReaders.Any())
        {
            throw new ArgumentException("At least one input file currentReader is needed");
        }

        WaveFormat firstFormat = inputFileReaders.First().WaveFormat;

        IEnumerable<WaveFileReader> nonMatchingReaders = 
            inputFileReaders.Where(reader => !reader.WaveFormat.Equals(firstFormat));

        if (nonMatchingReaders.Any())
        {
            throw new ArgumentException("All readers must have the same WAV format");
        }

        WaveFormat = firstFormat;

        _inputFileReaders = inputFileReaders.ToList();

        _readIndex = 0;
    }

    public WaveFormat WaveFormat { get; private set; }

    public int Read(byte[] buffer, int offset, int count)
    {
        int currentOffset = offset;
        int totalRead = 0;
        int remaining = count;

        for (int i = _readIndex; i < _inputFileReaders.Count && remaining > 0; i++, _readIndex++)
        {
            WaveFileReader currentReader = _inputFileReaders[i];

            int readNow = currentReader.Read(buffer, currentOffset, remaining);

            currentOffset += readNow;
            totalRead += readNow;
            remaining -= readNow;
        }

        return totalRead;
    }

    private int _readIndex;

    private readonly List<WaveFileReader> _inputFileReaders;
}

JoinWavFilesIntoWma.cs

// ...

List<WaveFileReader> waveFileReaders = BuildTheReaderListFromPathNames();

IWaveProvider joinedWaveProvider = buildProvider(waveFileReaders);

// This one causes Exception
MediaFoundationEncoder.EncodeToWma(joinedWaveProvider, _joinedOutputFile, 48000);

// ...