New Post: Same format - Mixing WAV channels

You can´t mix files with different wave Format directly.

Ensure the following:

1) Same Samplerate -> Resample with Mediafoundationresampler, WaveFormatConversionStream etc.
2) Same bit depth -> Use a Sampleprovider for your conversion, e.g. WaveToSampleProvider etc.
3) Same channel Count -> Use a Sampleprovider for your conversion, e.g. MonoToStereoSampleProvider etc.
4) Same Format tag (I think this is optional as it doesn´t affect the data directly)

Conclusion: Better work with sampleproviders for Mixing purpose. Hope this Points you in the right direction.