Sorry for the title, but I'm a little frustrated. I bought a new 2015 15" rMBP about a week ago, and have been using Logic Pro X to record - yet I get crashes pretty frequently..this also occurs with PDF Reader - just from reading/annotating a textbook. Also large textbooks can become choppy. For the past half a year I've used a Surface Pro 3 connected to a dock, and have had zero issues recording audio. Also PDFs were smooth and didn't have the choppiness of the 15". Is this an El Capitan issue? I love the computer, but really didn't expect windows to be more stable..