Shuz, I read both of your posts today ref. your third attempt. I can't believe they would send you back this weapon without a proper test. On the other hand, I give you credit for not being an idiot also. That being said, the only thing I can think of that may cause those FTFs, stovepipe and erratic ejection of the casings, all together, might be one thing you could be doing without knowing it and I actually doubt that you are. First, I noticed that my casings do cover a lot of ground when ejected. So, to the possible but not probable problem. If you were accidently riding the slide with your offhand thumb, that might prevent the weapon from going completely back into battery when squeezing off a round but once you adjust your grip for the second try it could go into battery and fire. If you are riding the slide with the thumb it may also affect the ejection process. Again, I give you credit for this not happening, but engineering wise offer a possible explanation of what could be happening.
Good luck