I am nowhere near being a radio guru and have no idea why or if you should use two receivers. But, did you try binding them in the plane, one at a time with the other rx turned off? Since the point of this 2.4 thing is to only be flying one receiver/setup at a time, it makes sense that trying to bind two rx' together would cause problems. Doing them independently would be the same thing to the system as binding separate planes.