No, I am not running hijack. I'm running 2b11. I mean rebooting by pulling it out of the docking sled and putting it back in. In my case, I know it is not the temperature because it has happened in very mild conditions, like the middle of the day on a 60 degree sunny day. There hasn't been any pattern to it. It also never happened until I put in the second drive.
There was a thread a while back about a time-out problem where certain drives wouldn't spin up fast enough to be seen. If I remember correctly, I thought you could adjust this in hijack. Since it's been an infrequent problem and so far has always worked on a reboot, I haven't yet gone to trouble of trying to figure it out.
Bill