I'm just back from a 5.5 mile walk and was checking my calories. I used about 110 resting calories and around 113 active calories. Well, I walked with an average speed of 4.2 ml/h which is slower than usually. Typically I'm around 4.8-5.0 ml/hour. Something is wrong there. Before the software upgrade I had ~650 calories for 5.6 ml walk, but slightly faster. Firmware version 21.19.