When you state you put a 2 dot setup, did you just use a standard M9 rear sight?
This is the sight picture on a standard 92 - Sight picture #3:
Even with a 2 dot setup, you need to COVER the target with the front dot.
If you used some other type of rear sight, you need to try an get a standard M9 rear sight (the 92 and M9 actually use the exact same rear sight now - they just put the white paint into a different location)