Hi! Sooo, I have this weird issue where my iMac (specs at the end) randomly freezes completely. It usually happens when using FCPX, either editing or exporting, but since I do video editing most of the day... I don't really know if that's the cause really. System suddenly drops speed to like... i don't know, like when a game goes down to 1-2fps and you know something is wrong... then it freezes. Doesn't matter what I do, it won't respond, I have to hold the power button until it shuts down and manually turn on again. My work consists on FCPX and the library is in an external Thunderbolt RAID0. So far none of this freezes have cause a data loss or similar, but it scares me... Any ideas what might be going on? Thanks! * Specs: 5K Retina iMac end-2014, i7 4GHz, 32GB RAM (16GB original from Apple, 16G installed by me), 512GB SSD original from Apple, Radeon R9 M295X. EDIT: This had never happened to me before. I formatted and installed Sierra from scratch 1 month ago or so (I was still on Yosemite... yeah). Didn't start on day one, maybe 1 week ago.