I have connected BT headphones and I started on my FR 255 running at the saved course.
course navigation gives directions on BT with an accuracy of 1/1000 meter! It is extremely annoying!!
At almost every turn I got a audio promp to turn in for example 25 m and 357/1000 m
Accuracy of up to 1m for navigation is sufficient
I use metric system, and polish audio settings. FR255 v. 22.24 , garmin connect 5.11.2