Omni firmware ver. and HW rev. for PT12

I just tried an older Omni with my rig (see sig) and PT12 hung at Initiallizing Audio Engine. This Omni was so old, it didn't have Reset in the Setup options on the monitor encoder display. I have a new Omni that works fine.



What is the minimum HW revision no. and minimum firmware version required in an Omni to work with PT12?