Some users of Gamin , Sony and Suunto GPS devices have been reporting inaccuracies in their GPS data as of new years day.

Users are reposting GPS offset, where a GPS track does not align with the actual route taken. The offset can be from a few meters to a few hundred meters, and is affecting devices with a Song GPD chipset.

Some of the infected devices include;

  • Garmin Edge 130, 530, 830, 1030 plus models.
  • Garmin Forerunner 45,245, 745, 945
  • Garmin Fenix 6
  • Garmin Vivoactive 3, 4
  • Polar Vantage range
  • Suunto range
  • Some Samsung phones

What’s caused the problems?

The issue is related to the EPO (Ephemeris Data File) – sometimes called the Satellite pre-cache file, that the device uses to quickly find satellites (it assumes their position while trying to get a more accurate lock)

This file is downloaded and updated via the internet whenever your device can connect to the servers to obtain a copy. But at the turn of the new year, the data in the file was wrong and this has lead to the offsets people are seeing.

The file has been corrected now, and next time your device downloads the file it will update it’s cache.

If you’re outside for long enough and your device can lock directly onto the satellites, that will also correct the offset.

So TL;DR – it’ll fix itself over the next few days.


What are your thoughts?

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