Windows 8 wont shutdown when Syncback runs at shutdown

Hi. I have SyncbackSE V5.20. I have it set to run on shutdown and this worked fine with Windows 7. Since I upgraded to Windows 8 it stopped working. I hit shutdown, Syncback runs, but then i am returned to the desktop after syncback finishes, rather than the computer shutting down.

This is also true of Syncback V6. I am testing that and get the same result.

Any help for a fix?