I don't think conversion quality is so important because the
proposal is a remedy for uaudio and auich.  An important thing
is to enable to *open* /dev/audio for uaudio or auich, not to
*use* 8kHz mulaw.  The resultant sound of 44.1kHz -> 48kHz
conversion has no problem for my ears :-)
# I have nerver tested 48kHz -> 44.1kHz conversion.

Anyway, I'm going to commit the patch at 14:00 GMT Thursday
without sound quality improvement.  If one has an improvement
idea, please post it here.

-- 
TAMURA Kent <kent2002@hauN.org> <kent@netbsd.org>