Formula (Gerber soothe)

My doctor recently switched my son (Dob 11/3/16) from Similac sensitive to Gerber soothe. My son was not having good bm, so he suggested something similar but still for gas.

I have never had an issue with him spitting up until now. He was consistently drinking 5oz every 3-4 hrs on the Similac and now he wants 5oz every 3 hours (but is spitting up .5oz every time).

I've made sure it's measured right, taking breaks, burping, etc.

Anyone else have an issue with this?