What would cause my AFR to be a half point off?

[QUASAR]

I'm running a Innovate LC-1 wb with hookup to XD-1 guage and logging via HPT EIO inputs. HPtuners consistently reads about .5 higher a/f ratio than the xd-1 guage will display. Car runs 12.4-12.5:1 afr on the guage at WOT, and 13.0 in HPtuners. What would cause this? I am using the predefined configuration for the LC1 within HPtuners.

[Arron]

I have read somwhere that Innovate have more than one calabration for there LC-1

[QUASAR]

That could be a possibility. And would make sense. It probably would be a simple -.5 to whatever the current formula in there is. I will check into it, thanks!