Blue smoking MMM

[BrianG]

Theory:

Poor connection on the EC5 connector which created resistance. That resistance created a voltage drop when large currents flowed which then caused lots of heat to melt the solder. That same resistance appeared to the ESC as a poor quality battery (high internal R) which increased the amount of ripple currents which stressed the caps too much and heated them up as well.

The blue stuff on the heatsink was from the explosion of an unfortunate nearby Smurf. Sad really, but they should know better.