Yes omnibus nano.
And I had a problem calibrating, too, but assumed that was universal at the time, and not related to the omnibus nano.
I had to enable the old ‘live calibration’ mode in mission planner. You hold down control or shift or something, when you click the “compass” menu item in mission planner. (Sry I don’t remember which modifier key it was, but try shift, ctrl, alt, etc). Then MP will show the old live calibration w/ the crosshairs. It ran successfully. Then after it ran, I was able to run the ‘onboard calibration’ w/out any trouble.
And, you do want to run the onboard calibration… It does more than the old live calibration.
-there are a couple posts about it in this thread from Sep14th if you want to read a little more about it…