Well Jurgen, I like Audacity too. Indeed, that's the way I'm doing it now. But I need to insert this process in a automatic chain of processes that is made entirely in PD, that is the reason of my obstination in that specific point.

I'll try the -batch flag. That will be useful not only for this but for the entire process. How do I make it work? Just putting the -batch flag on startup?

One last thing. I remember to have some synch problems while recording with many [writesf~] (correctly triggered, of course). Any ideas about that? I might had been doing something wrong…

Thanks Ignacio