Hello all, I was wondering if someone with a little more mac knowledge may be able to help me. I have a mid-2012 macbook pro that seems to be really badly affected after upgrading to Yosemite. It's a work machine and I'm really reluctant to do a fresh install at the moment as I'm in the middle of a large project. A few of the problems I'm having - 2 min start up time (similar at shutdown), at startup (and wake from sleep) sound is locked until headphones are inserted, sometimes when waking I get a black screen that forces me to use the power button to shut down. Everything is laggy - folders opening/closing, switching between apps. It's just not the mac experience I am used to. I'm sick of the beach ball. I thought it was Apple's way of asking me to upgrade my machine but then I installed Yosemite on my old MBP (2008/9 I think) and it's smooth. Infuriatingly smooth. Then here I am gritting my teeth all day on what should be a newer and better machine. I've tried lots of suggestions from google - delete sound folder, uncheck 'put hard disks to sleep when possible', turn off transparency etc... but no luck. Is there any way of finding out what's causing my issues without reinstalling everything? I don't have applecare or else I would have called them by now. I'm sensing the only way (with this many issues) is a fresh start but it's just such a massive inconvenience at this time. Any advice would be appreciated. ---------- and sorry about "Horrendously"