I have a v1 board and all servos run free Thanks for the hint, i'll try lowering the alarm threshold.

@Rongzhong Li i meassure 8,4V on the board. just came across your blog about the different 14500 batteries. I have no idea what batteries I have and if they are protected or not (noname product with no google-able information printed on it. how can i find out if they are protected or not and do you think this would explain the behaviour? on the other hand -> the same batteries worked yesterday for 10min and I have charged fully charged them afterwards?!

thanks for your quick reply. I've reuploaded wrtieinstinct.ino already and did all the calibration again... i was able to start the calibration procedure but the servos didn't behave as they did in the first round yesterday. e.g. when i entered c9 -5 then also other servos started to move and didn't stop till i've reset the board. nevertheless, i finished the calibration with the settings i wrote down yesterday. after that i compiled nybble,ino again but ended in the same issue -> alert buzzer and no reaction on ir remote anymore any other ideas why this has happened? could it be necessary to burn the bootloader again (it was not when i started yesterday)