My XD-40 performs flawlessly. Over 1000 rounds through it and not one malfunction. When I put in the EFK barrel to change it over to 9mm about every 10-15th round I will have a FTE. I have changed grip, made sure i am not limp wristing, changed ammo, and still very couple of rounds it won't eject the empty case. The case comes halfway out of the chamber and then stops, holding the slide open. I then change out the barrel and go back to 40 and no problems. Is there a problem with the extractor? Problem with the barrel? Any suggestions?