cordova-plugin-background-geolocation: IOS background - position changing very slowly?

Hi! This is more of a question on how to get as exact positions as possible when running in background on IOS (9.3). I do get regular position updates, but they change very slowly. Android works very well. So I wonder if someone have any hints on what to change or add?

I use these settings:

         desiredAccuracy : 10
         stationaryRadius : 20,  
         distanceFilter : 30,
         startForeground : false,
         interval : 60000, // Android
         locationProvider : <User can switch between both options>, // Android
         activityType : <I have tried the 4 different options>
         pauseLocationUpdates : false, // IOS
         saveBatteryOnBackground : false // IOS

Cheers -jo2