I had this problem and completely resolved it by changing the plug ins to the receiver. Rather than the setup as in the instruction book, use this setp: plug 1-4, 4-1, 2-3, 3-2 and your problems will go away. I use a Futaba Skysport aircraft radio that I modified to remove the ratcheted left stick.

Here's some pics of my KT. I just addded the photo etched grilles and tha's all I'm doing to it.