945 HR inaccurate during workout - any ideas?

scarfecycles said:

Does Garmin know about this? Is it based on software/firmware and has someone found a solution? If not, what is Garmin doing to support users who are struggling with this issue? 

As always, the best way to find answers to those questions is to contact Garmin Support yourself (which you apparently did). The more people that report the problem, the more likely they are to do something about it.

Garmin also says this about the sensor:

"in periods of low activity or rest the sensor operates on low-frequency sensing mode, but switches to higher-frequency sensing as soon it detects increased levels of physical activity...sensing functions continue to operate ceaselessly and with unstinting precision all through the day."

This is a very helpful and informative forum. Thanks for sharing.

To recap, I have had my 945 since last August, and WHR worked during recorded activities, and I did not notice any HR discrepancies, but I also was not broadcasting my HR at the time. During winter, I began broadcasting my HR to a rowing machine and noticed that it never went above 110, despite clearly being much higher. 

I contacted Garmin and they are aware and added me to case #, and sent me a chest strap (which I do not prefer to use). Due to suggestions in this thread, my workaround is to start recording an activity on my watch, in order to broadcast an accurate HR, and then not save it and delete it, in order to avoid double-recording my activity, since the rowing machine is also linked to my phone via an app and uploads the workout to my Strava. 

Also, I tried a newer FW beta 4.06, which did not seem to fix anything. Just recently, I received FW 4.10 but I have not had a chance to test it. I will update here when I do. 

By what I read in the other thread, the 945 and F6 lines share the same HR hardware/software, and many watches (but not ALL) are showing the same problems. I will follow that thread as well.

Thanks again!