Hi, I using nrf52810 with custom BLE profile and 4 sec advertising + continuous RTC. Device is battery powered (750 mAh) and PMDC motor equipped. Most of time (90% of day) it sleep with sd_app_evt_wait continuously checking state if turn-on button or connection of battery charger or BLE connection. After 8..20 hours of sleeping the firmware crashes. Within 3 hours after reset it dont crash.