FR255 Music on 27.09 and I'm not sure what to make of the HR data.
This is on the same run, with a 965 on my other wrist, which I think is a better reflection of my HR during this run, although I'm not entirely sure. Maybe the 965 is incorrect?
The 965 is also on FW 27.09 and the same system component versions as on the 255, including WHR.
Garmin, please send me a chest strap so I can test and see which of these two watches has the more accurate HR readings 
And the 255 Music on a different run and route, on firmware 26.08, which seemed ok to me, based on what I'm used to seeing for that route. No sudden spike.
I know it's not officially supported, but I'd like to roll back to 26.08 to see if it makes a difference. If anyone has the firmware file please share it
