K8098 - 2 modules nit reading the same values

Hi all.

I recently purchased 2 kits that I built at te same time (mirror). They seem to operate perfectly but when reading values from a resistive load, there’s a difference between the 2 modules.
I mention that both are supplied by the same power supply, with the same wire length and connected on the same load.
Any idea of what to check ?

Thanks