My little man was having the same problem, it seemed right from birth when I was nursing him and through bottle feeding as well. He would be SO frantic for the bottle, chug the first few ounces, and then pull off and cry. I could tell he was still hungry but something was wrong. I heard everything from "he needs to burp" to "he needs to spit up", had him on Zantac as well as soy formula for a while. But I really didn't think he had reflux because other than at feeding times he was a very happy baby! I had been using the wide nipples that are supposed to be more like the breast. One night I was so desperate I tried a bottle I had in the closet that had the old fashioned skinny nipple. And he fed a little better. So I switched to the regular nipples (I use Playtex ventair bottles) in the Stage 2 flow and gradually (over the next few days and weeks) he stopped having feeding problems. I dropped the Zantac and returned to regular formula. He now eats 7 or 8 ounces in about 5 minutes, and does this 4 times a day, sleeping through the night (with a paci and swaddle, but that is another topic altogether!). Now you might have already tried every nipple out there, but for me, using the regular nipples completely solved the problem. My little guy just doesn't want to work that hard for his milk, which is probable why nursing didn't work for me either. I guess I have a lazy little sucker :wink: Hope this helps someone.
P.S. And for some crazy reason, he likes to eat laying flat, like on the couch or the carpet.