Well, you do know more then anyone I ever met about the electronic part of hard drives. And I'm very thankful for your help and patience. And we can now rule out power supply issues. The question is then.. was this just a fluke? Or the OS which runs on the NAS, had a mind of it's own? Or the SAS controller? When I think about the SAS controller, I start to think about the lanes. That would be very hard to debug, or troubleshoot. I'm not sure if I want to dive into that rabbit hole.