I am running the demo, and I am finding that anytime I move a control on the GUI the CPU usage in logic spikes causing crackles. After a few seconds the CPU usage goes down to normal again.
This only happens when I move a control. The rest of the time the CPU use is fine.
Logic 9.1.7, OSX 10.7.3, Macpro 8 x 2.26, 16gig Ram