Just over an hour into my bike ride today while I was slogging up a steep hill, my Polar CS200 heart rate monitor rebooted. The screen went blank, a few cryptic symbols appeared on the display, and then the display filled with a union of all possible characters and symbols that it ever displays. And it stayed like that until I turned it off and on again. It forgot the ride data up to that point for the day and all the general settings, like the current time, but kept all my personal settings. I’ve gotten use to the sensor strips on the chest strap sometimes not immediately picking up a signal, but I’ve never had the software crash like that before.