I don't have a solution, but I'm hear to say I know exactly how you feel and sympathize with you.
My nearly 4 month old daughter brings up her feed regardless of the amount or time of her last feed. Often she's still spitting up at the time of her next feed. Sometimes it's like water, other times it's curdled and sticky.
I've tried burping her heaps (she rarely burps), sitting her upright during feeding, sitting her upright for at least 30 minutes after feeding, making sure I don't give her tummy time until before her next feed and only changing her nappy right before her next feed (if possible).
Only advice I can give you to stop the outfit changes... buy lots and lots of bibs. The plastic backed ones last longer, but I can go through up to 8 bibs with her a day - and have spew rags on hand everywhere!!
I did the same thing and expressed my concerns with the nurses (multiple times) but since she's still gaining weight and isn't in pain, they're not worried at all and say it's just a part of her nature.