Since upgrading to v13, like others, I have seen issues with how the watch works during activities. In this case, indoor cycling. The watch will be at a high battery level until the activity is started. Then it immediately reports 4% battery. As the activity proceeds, i see the battery percentage on a custom data field screen INCREASE. This continues until the banner for reaching each increment of 5 miles appears. It then immediately reports 4% again and starts the process over. Finally, when the activity is over, even though it may report reasonable battery levels before the end, it shuts down after saving.
I do not get the restarting that others report during the activity.
Sensors:
Garmin Ant+ HR strap
Garmin GSC10 speed/cadence sensor.
