Hi again ...
You might have a look at sox (which also comes with
soxmix) - I'm not sure
if it is actually able to mix two sources to different channels, but since
you asked for a scriptable audio editor, sox has been the first thing that
came in my mind, as it is scriptable as in shell script.
I've read the manpage
two times now. soxmix is able to mix two different
audio files into one but all I got until now is both languages totally
mixed up in a stereo file. Maybe sox is unable to seperate them, maybe
my english is just not good enough to understand the manpage.
Cheers
Thomas
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