System changes startup drive after SD backup
 

Seeing something weird the last couple days... I have SD set to clone my iMac hard drive every night at 3 AM and then shut the system down. Which it's done, flawlessly, for a couple of months. Two nights ago, somehow, in the middle of the night, either SD or my Mac decided to start setting my backup drive (a LaCie D2) as the startup drive before the system shuts down. Which means that when I boot up in the morning, the system boots from the LaCie drive; I then have to switch my designated startup drive back to my iMac's hard drive in the preference pane, then reboot. This is annoying, to say the least.

I do have SD set up to shut down after cloning, but not to reset my startup drive. (As Dave has pointed out in an email, there's no way to set it to do both.) And a reading of the log for the scheduled operation doesn't show anything out of the ordinary.

Dave has this pegged as a Mac issue, not an SD one. Just wondering if anybody else has ever experienced this weird behavior... Thanks for any input.