access to MCI record buffer? (for mp3 encoding)

I'm using Idael Cardoso's "yeti" c# lame_enc.dll wrapper for encoding mp3, and it works great. It compiles to 2 additional dll's, which is cool because I can link them to my project without staring at 50 files in my solution explorer. So far, I've been recording audio using mciSendString, which is easily saved to disk. Then I run the resulting .wav file through lame, and end up with a working .mp3.

However, I noticed in the docs for the WaveStream class that it is overloaded to handle both filenames, and System.IO.Stream, which would be better. That leads me to 2 questions:

1) How can I get control of MCI's record buffer on a per-recording basis without having to save and load a physical file?
2) If #1 returns a pointer, which I'd imagine it does, how will I convert that to a Stream object?