Interesting, because this appears to be a firmware issue, not hardware.
Nevertheless, have you tried the usual shenanigans while troubleshooting memory installation issues? Reseat the RAM, swap the sticks, use the other 2 slots, use mismatched slots, use one stick at a time, etc.? What has been the difference in behaviour, and the RAM readings reported?
Edit: And on a lighter note, congratulations on getting your RAM running in a RAID-1 setup