There have been some concerns about GPS accuracy and reliability. I've seen this discussed over on the Scenic navigation app board, too.
The author there has suggested downloading an app called "Altimeter & Barometer" to check people's phone GPSes. Note: this is an iPhone app.
https://apps.apple.com/mx/app/altimeter-barometer/id541514339?l=en-GBI would suggest to run this app on the phone, not via CarPlay and have the Chigee main menu displayed so you can then compare each device's GPS receivers.
It may or may not help. I don't know. Better than nothing, I guess.