So a bunch of little things started randomly happening with my Macbook Pro (2009 I believe). Everything runs fine for a few hours usually and suddenly the CPU will randomly start maxing out with no processes running, applications will randomly crash/stop working/not start when you click on them. Nothing I could figure out to stop this except restarting computer. When I log out or try to shut down the screen goes black except for a pop-up "Security Agent Unapproved Caller". I'm not able to click it away so I have to force the computer off. After restart things will work fine for a while before they reset. I've booted it in safe mode with same results. I've started using Ubuntu which tends to work better.... but it will still have the same problem happen (applications crashing or not starting) and every two days or so I have to run a manual fsck on the hard drive in order for it to work. Not sure if I just have a really annoying virus or the hardware is simply failing.