CPU usage in Perform Mode

Recently I switched from an i7 2.7GHz Macbook Pro to a Mac Mini (the i7 2.6Ghz). Both are quad core so I expected almost identical performance, but I'm noticing that when I go to perform mode on the Mac Mini, CPU usage doubles immediately - and that's just idling. When I play, my most demanding patches can be pushed into audio glitch territory, which is not something I want to be near for a rock solid gig setup.

I am running Mavericks and MainStage 3.0.4.

Has anyone else noticed a CPU difference between Edit and Perform modes?