I can try that. My thinking was that since the aiff mix works without the plugin, the builtin synthesizer BIAB uses (from the Mac?) must be routing its audio to some appropriate place where it ends up in the mix when I do the Save Special...aiff . So, if I could only route the software synth (Kontakt) to the same place, it would be saved in the mix as well. And the Kontakt "Natural Sounds" sound so good!