Hi, Nybble (NyBoard v0_2 + RasPi 3) was running now for several weeks without any problems. Today something happens: - Nybble was directly connected to my external power supply and RasPi was connected with USB (I used this configuration in the past few days without any problems) - I called "./ardSerial.py khi" from RasPi and Nybble started greeting - During greeting suddenly the cable of the external power supply drops out - Followed by an undervoltage meow I disconnected everything and tried to restart Now Nybble doesn't boot up when powered. No servo moving, no rgb led, no initialize beep, no undervoltage meow, only the buzzer hums arround in an annoying constant frequency. What should I try next? Burning the bootloader, checking something on the Board or ordering a new one?