Hi, I just did the calibrate ESC and auto level calibration again and now it is less of a problem.
The ESC's also did make a different sound sequence when calibrating as far as I remember.
So you might try this step again, maybe you had a similar problem (one ESC not calibrating or something like that).
BTW: only ESC that becomes slightly warm is the no.1 which is also used (with a red lead) as power source for the transmitter and yaw servo.
Edit: it was not powering the yaw servo, OUT1 and OUT2..OUT8 have different power circuits:
Connect one ESC with BEC to OUT1 (motor 1) to power transmitter and KK2.
Connect 1 ESC with BEC (typically motor2) to OUT2....OUT8 to power the tail servo.
I've disabled (folded back and heatshrinked) the third ESC BEC power line.
Edit: and reversed one of those changes because of the reason mentioned above: you need a second BEC to power the servo, so at least one of the OUT2..OUT8 ports should be powered by an ESC with BEC
It was not clear if my ESC's (Turnigy Multistar 15 Amp Multi-rotor Brushless ESC 2-3S) could handle parallel connection to the KK2 (the KK2 power bus is linked through on all connections (although OUT 1 is separated from that), so all BEC's from the ESC's would be providing power at the same time. Some ESC's allow that, some don't.