Firmware 19.18. When the dynamic switching of sources setting is disabled, the optical heart rate monitor
continues to work (or rather, it is no longer constantly on, but blinks frequently). When a workout is
running and the chest strap is connected. The same thing happens
if you just turn it off (turn off Auto) - it doesn’t go out completely, but blinks often. The heart rate
display says that it is disabled. After turning the watch off and on, the same actions completely turn off
the optical heart rate monitor, but after about an hour everything starts again. What is the reason?