[orbro]

If you're using the 2626 I'd say no, it's not possible. The Profire has been very buggy here and causes cpu overload errors while recording one track with one reverb plug in at 32 samples. At 64 and higher things seem to be a little better though. I too am using a 8 core Mac Pro and the cpu usage meter never goes above 25%.

The first thing that would help is to get a separate firewire card for your interfaces and run your hard drives off of the built in port. The second thing you can do to increase performance is to disable any software returns that you're not using in the 2626 mixer window. Also make sure you have the "ignore errors" box unchecked in the playback engine window. Good luck!