@g3gg0: During one of my first recordings with mlv_snd, my 550D camera locked up (got a "busy" text, sorry I don't remember the exact wording) and apparently the sound file didn't get written properly: I get a "Received AUDF without WAVI, the .wav file might be corrupt" message after all the .dng's are (correctly, it seems) extracted.
Despite this, the .dng's look fine and the length of the resulting .wav file is roughly what one would expect for a 40 second (at 25fps) clip. Of course, it is corrupt, as its metadata indicates "MPEG AAC Audio at 7350 Hz, 28kb/s" instead of the correct "PCM S16 LE Stereo 44100 Hz, 16bps (from VLC player)" as on my other clips.
Question: is it possible to rescue this .wav clip by inserting a WAVI block into the .mlv file, or by hex-editing the .wav itself to correct the header? [Update: SOLVED! See two posts down]
In any case, thanks again for raw with sound, it's a quantum leap in usability and enjoyment! Cheers.