Brown Sugar Oat Milk Shaken Espresso Always Foamy :(

Hey guys, ever since I started working at sbux I noticed there was always a lot of foam after pouring into the cup before the oat milk. I literally have to scrape the foam off the top and add more oat milk every time. Is it because I’m pouring the shots into the shaker with ice in it already? I’ve seen baristas on social media put the shot in the shaker first and then the ice? Or is this just a universal thing?