Hi, Dranok.

I am also very interested in encoding things in mono and I usually just do that on my systems (where I am using some form of Unix exclusively).

For instance, *right* *now* I am recording some content from some tapes of mine using sox and taking the audio from my sound card. I have about 40 60-min tapes (which means approx. 80 30-min files to compress) which I am saving in stereo.

For the encoding, I'm usually using lame's -m m and one of the variable bitrate levels. I have been getting very good results.

Also, I have taken some lectures from MIT's Open Course Ware that are recorded in RealMedia and I'm converting them to Xvid+mp3 and forcing the audio to mono. The audio part is usually encoded at 50kbps--55kbps when using something like the preset=extreme quality.

So, I don't know if you're seeing any isolated problem or not, as I am constantly testing lame with mono encodings.

If you could provide any particular file that you're having problems with, I could try to investigate things.

Regards, Rogério Brito.