I think Govert may have got it right there, looks like you have soldered your orange and blue motor wires incorrectly, which would account for the sporadic bursts and the wires getting hot. However as you don't show the back of the ESC it has hard to be 100%. If you could take photos and PM them to me we can sort this out pretty fast. Just make sure you take a photo of each element ESC (where the wires are soldered), receiver and the motor and that they are very clear.