I recently picked up a spektrum dx3r and when I set it up the first time I had a "moment of What The!?" Then, unknown to me until I read the manual, there was a way to calibrate the potentiometers (guessed spelling) but you basically calibrated the radio to full right, full left, full throttle, full brake, and neutral.

Double check that since your spektrum. It was new to me as my old M8 didn't have that option other than "trimming" them or setting endpoints manually.