I have just been in the process of making the rc explorer v2.5 tricopter and everything seemed to be working when i first tested it, except the servo, it centers, locks up, and does not respond to any input at all. I have checked that it works by plugging it directly into the receiver and it works fine. The servo is a analogue fake Futaba standard size servo so it is cheap but does work, and the kk 2 board is set to the tricopter so I have no idea whats causing this. This is my first multirotor so I don't really no what i'm doing, just following instructions, so it would be really helpful if someone could tell me whats wrong with it / me.