I see there are more ppl with rb912 problem using both cards.
http://forum.mikrotik.com/t/is-there-a-stable-working-mini-pcie-3g-modem-with-rb912/72332/1
http://forum.mikrotik.com/t/912uag-2hpnd-dont-work-minipci-wifi/73947/1
so maybe Mikrotik staff will do smthng about it?
My 4 pcs of rb912, are gathering dust on the shelf as for now.