A couple a days ago, probably after the update to the 7.20 version, watch started with problems on the broadcast hrm to the garmin GPS.
It will loose the connection to the GPS after a couple of minutes, if i stop the broadcast and restart it the gps will pick it up, but happens every couple of minutes. I've tried the reset of watch, removing watch faces and widgets, etc, but to no avail. I've tried with the watch and gps while seating / stopped and also while ridding, but there's no difference.
If i use the hr chest strap with the edge 530 it will work flawlessly.
I've seen some threads about this and seems to affect some watches from various versions of fw since a couple of years ago, but no conclusion as to wether it was solved or not..