libquicktime (it is an obsolete function the libquicktime folks want to
get rid of as soon as possible). After asking on the libquicktime mailinglist
the replacement for quicktime_read_audio() is lqt_decode_audio_track().
A similar function exists for writing audio (lqt_encode_audio_track).
One VERY important and useful side effect of using the lqt_{encode|decode}_audio_track
routines is that they handle the endianness of the data - the underlying
libquickime routines know about flipping the bytes and thus that logic can
disappear from lav_io.c
