I don't think this is a fcpx issue, so I am posting it in the Mac OS forum. I got a USB 3.0 256 Lexar drive and formatted it for Mac OS using disk utility in Sierra. When I use it in Final Cut Pro, it seems every few minutes to hang for a while (like 15 seconds), and I get the beach ball, then it wakes back up and allows me to keep editing. Aren't these drives supposed to not do that? Am I missing something?