I own a Macbook Pro w/ Retina from 2012: 2.3Ghz, 16GB RAM, SSD. I've noticed Garageband having to pause and load a lot (rainbow wheel of death) when I'm mixing MIDI in Garageband. I have about 20 tracks, all using an instrument from East West Symphonic Orchestra. My question is, it Garageband having a hard time or is my computer not able to handle this? Would upgrading to Logic help?