Do you use soy or alimentum formula and why?

My baby has the hardest time releasing gas, he’s up all night just straining and grunting and doesn’t sleep at all. I’ve tried so many different formulas (all Similac brands - pro advance, sensitive, total comfort and soy). Total comfort he spit up SO much and the doctor said if that’s not working then try the soy and it seemed to help him release gas the first day on soy but by the 2nd he was back to having difficulties and he’s just been constipated.

We’ve tried gripe water and all the gas drops and they just don’t work.

I know I need to talk to the pediatrician again but just curious if anyone else has had a similar issue and what formula worked for you? Should I stick out the soy a little longer? I’ve heard mixed reviews on soy.