I have a problem with my 735xt. Heartrate is way off. I bought the 735xt in march and from the first run it showed weird heart rates. While running rather slow (like jogging), heart rate went up to > 180 rpm back. Differenz to real heart rate 40-50 bpm. There was no reasonable vo2max etc.
Set back everything, worked once, same issue again.
Sent the 735xt to service, received a new one. Worked one run, same again on second run.
Reading the forum gave me the idea that the problem might be the 9.40 software. All problems about heart rate measuring were reported after the roll out in octobre 2018.
Problems seem to pile up during the cold month. Temperature could be a part of the problem too?
PLEASE fix it !!
My 235 never had a problem like this for more than 2 years and 4k running km...
I am very disappointed; I expected an improvement stepping up from 235 to 735xt
Curios: No problem with biking, just with running.
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