The following code works with some wav files, but with others I get, \"InvalidOperationException was unhandled. Message=Sound API only supports playing PCM wave files.\"
The way to do it is to use newkie's code at: http://www.codeproject.com/Articles/175030/PlaySound-A-Better-Way-to-Play-Wav-Files-in-C?msg=4366037#xx4366037xx
In my case, at least, I had to change all of the lowercase x's to uppercase x's, though, to get it to work.
So, do you want to PLAY the file or CONVERT it ? What is the primary goal ? Do you play it as a prove you can convert it, or do you convert it because you don't know how to play not-converted file ? http://www.catb.org/esr/faqs/smart-questions.html#goal
Your question's title claims "convert" but the body claims "Play"
This answer is about playing files.
You also may try to use FFDShow codecs directly without DirectX intermediate. http://en.wikipedia.org/wiki/Libavcodec and http://libav.org/ and http://ffmpeg.org/ (they recently had a schism)
Googling for "FFDShow dotnet", "libav dotnet", "ffmpeg dotnet" shows a bunch of libraries to use it, such as
There is also BASS library. It is targeted as sound playback during gaming, so it probably has less range of formats and not much for re-coding. Still many music players are built on top of it. Some says it is the most simple API to use. So it worth considering. http://www.un4seen.com/
http://MediaInfo.sf.net is a library (native win32/win64 DLL) allowing to check most multimedia formats content. I don't know if using tis C or C++ APis is easy from C# side.
Look at audiolab library from mitov. It works great