Hi all, Having a really annoying problem with El Capitan and my 2015 15" MBP (dGPU). 100% of the time, if i take my MBP in sleep mode (clamshell) and plug it into the charging cable and external monitor, and then attempt to wake the MBP by the using the external keyboard/mouse the entire system freezes and I have to hard reboot it. Sometimes i'll get this strange artifactual log in screen that I cannot type anything into, sometimes it's just a blank screen, and sometimes I'll get a windows login screen with an indefinite beach ball. I recently turned on FileVault for my SSD along with having users log in when I wake from sleep, so maybe this has something to do with it. I see a lot of error messages relating to WindowServer in Console around the time it happens. Is anyone else having this issue? I'm using the older Aluminum Apple Cinema Display (30") connected via thunderbolt adaptor. I have no problem sleep/waking it if the MBP is already connected to the monitor when I sleep and then wake it. It's only an issue when attempting to wake the computer after I plug it in to the external monitor.