AeroPod, PowerPod and Newton

I have downloaded ride analysed it in Issac and finally merged with GPS data from my head unit. But resulting export csv has some of timestamps doubled at the beginning of a ride and some in the middle.
Source gpx file has no duplicated timestamps. It wasn't much to fix so I have cleaned up the resulting file in Golden Cheetah.
Gpx with HR data was created in Oruxmaps but forum doesn't accept gpx files for upload.

I attach ibr and csv created in Isaac.

Personally I would not worry about this.

The GPS file merge in Isaac compares the speed/location data of the gpx file with the speed data of Isaac. Sometimes there is an imperfect match, in which case Isaac does its best to make a good guess.