My DS2 was a massive chucker - I had a huge supply and forceful letdown and he was 8.5 weeks prem and tiny, so we had a few issues!
I would express a bit before each feed, I block fed him, fed him in an upright position and I used a thickener at some feeds (I don't think this is in vogue any more, but an old friend who's an LC recommended it and it helped).
I did all of the above for about three months and then he just seemed to grow out of it.
He's turning one at the end of the month and is still a boob monster.
Definitely turn to the ABA for support - I'm sure that things will resolve themselves