Pace not accurate when using datafield indoors without gps

Hi

I have a problem that a user reported a problem when using my datafield indoors. He has a Fenix 6x Pro and calibrated it with some outdoor runs. When he uses it indoors pace is always above 10min/km (upper limit to display), but strangly the distance is displayed correct.

Does anybody else have this problem ? Or how to fix it?

I just take the info.currentspeed to calculate the pace. Do I have to take another value when gps is not used ?

thanks

regards

Erich