I had a problem similar to this myself and could not solve it.
There was something buggy with the OS and/or RST.
Whenever I would shut down my computer, RST would not be stopped cleanly, and the next boot up virtually guaranteed a rebuild status.
I was not really offering a solution as much as a diagnosis.
I moved the array to another machine, and that was my solution.
In your case, since Standby is involved, you might want to upgrade your BIOS because standby issues can be caused by bugs lurking there.
If not there, then perhaps a driver on your system is causing it, so you might want to updates those as well.
If that fails, there are still lots of possibilities - your power supply, some other hardware and/or software conflict - it could take a long time to figure out the cause, and there might not be a cure once you find it.
This is why when strange things like this issue happen, you best be ready to either: 1) spend a lot of time playing with your system. or 2) give up and use a different system.