first time i turned it on

all i was doing was centering and putting the horn on my steering servo

the servo was making noise and then POOF BEC BBQ

this in on a tekno converted MBX6 buggy with mamba max pro and tekin 2050 sensored.

I have a 7955 on steering and an s9351 on throttle.

The BEC caught fire on the side where the inputs form the battery (4s) come in



Any idea waht caused this. I have another CC BEC but I dont wanna hook it up and try again if this same thing will happen