QuickTime Components

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Here's some info from Apple's QuickTime engineering group, from internal
bug
ID 4049440:

"QuickTime's sound playback in QT7 is now based on CoreAudio instead of
on Sound Manager. Therefore the Ogg Vorbis decoder ('sdec' component) is
now being invoked from a CoreAudio AudioConverter via
SoundConverterFillBuffer instead of by means of the chain of Sound
Manager components used for playback in QuickTime 6. This is a different
code path into the decoder that all other sdecs we know of support.
"Vorbis is unusual because it makes use of audio blocks that overlap
in
time via low-level multiplexing. There is no direct support for this in
QuickTime
sound media. To force a fit, the movie importer that's part of Ogg Vorbis
for
QuickTime creates sound media that's carefully laid out to ensure that
blocks
are delivered to the sdec in the appropriate fashion via the old
implementation of Sound Media. It's quite possible that the expectations
of
the sdec are violated when the audio data is delivered to it via a
CoreAudio
AudioConverter. But we just don't know enough about how the Ogg Vorbis
components work to be able to say. [...] I believe that the developers
will
need to be involved for us to make progress on this issue."

From CoreAudio engineering:
"I'd strongly recommend that these developers write an Audio Codec and not

a Sound Mgr codec. Given that this is beta software, I'd recommend that
the
developers work with QT dev relations to resolve this issue."

--Jens Alfke (jens at apple dot com)