I've read a few threads in various places about this, but nothing to fix my problem: I'm running 20-30 EXS instances and having stuttering playback because one processor of my two (see my signature for hardware configuration) is overtaxed while the other sits around. I've looked at http://support.apple.com/kb/HT3161 which seems to make sense, but doesn't really apply to my situation, as I use minimal plugins on buses, auxes and outputs. I need to make some of my EXS instances use one processor, the rest, the other. Is this possible? Can anyone point me in the right direction?