If the connectors have no issue during chargeing it would lead me to believe that the issue is with the terminal crimps on the machine cables if the heat build up concentrated only in the area of the connector (an infrared heat gun would reveal this, your hand works too) run the machine hard ,check the temp along the entire length of the cable, if the entire cable(machine side) gets hot its too small for the current load. If only the area around the connector gets warm I would SOLDIER on new terminals( are these also being replaced after an incident? or is the plastic houseing only replaced )how big are your connectors? Are they possibly under sized?