My watch (instinct 2) seems to reports 1.6x the distance I walk on the treadmill (ratio of miles to km). E.g. 3 km would be reported as 4.8 km (as if I ran 3 miles). It notifies me when I do a lap every km correctly, but then uploads incorrect data. The SPM is consistent with 3km for my stride length as well, so I'm not sure it's a measurement error. Has anyone else had a similar problem?
I've set my watch to be metric, and I've also changed all the units to be metric here https://connect.garmin.com/modern/settings/displayPreferences
