I have the same kind of issue. I just use Kodi to play videos off of my external hard drive (same thing from any other drive I have tried). I will be watching a movie/TV show then randomly the circling icon for busy pops up then a few seconds later, I am seeing the black screen followed by the start screen of Libreelec/Kodi. Usually, when I get back to the video I was watching, it shows that I haven't watched any of it. Sometimes this happens shortly after powering up the unit and then other times, it is days after watching movies/TV shows. It seems very random to me. I have tried to reproduce the effect by watching the same video and I can't "force" it to happen. I am using a Raspberry Pi 3. I know I am using the Jarvis update, not sure of the number though. If someone could explain how to get the crash log, I could post that. I am still a newbie when it comes to all this. I just follow along with guides and things I can search from Google. I have uninstalled add-ons, reformatted the Micro SD card and changed skins, but nothing seems to change the randomness of the restarts.