First, thank you for your help.
It was rather...interesting. First, my system run 6 months without problem. I realized now that slot B2 wasn't working, it didn't show Corsair 32GB in the Bios but SpacemiT 2048 MB. I googled SpacemiT, it's a Chinese company producing mainly Risc processors, maybe one of the parts of the MB was from them. So it seemed that the slot was broken.
Just for giggles I installed the latest Bios for my MB and suddenly the Ram in slot 4 was working again. After 2 or 3 reboots iCue also detected it and everything is back to normal.
My best guess is that rebooting after installing the iCue update somehow corrupted the Bios and maybe iCue played a roll in it, although I don't think it would do anything on Bios level.
I might add that it is an AMD system and they are rather picky with Ram. After building it I had to wait for a new Bios that would detect my Ram and then for another Bios to make it work with EXPO enabled;-)