I was just looking through here and I saw your post. I bought a dx6i from a cx2 owner a few blocks from me that had the same problem on a 4 in 1 . Seems this is only on the dx6i not the dx7. He got it toned down a little by setting it up in Heli and the 120 swashplate and the gain turned down all the way. The tail still made flying a chore and as I remember he had no way to change the throttle curve. He sticks to RC Groups and seems this is a known shortcoming but there is a fix but I dont remember what it is. Might try the dx6i thread.