Mysta02

I got the Asus ROG Strix Z370-F for my recent build, which states 7.1 support on its product pages. It wasn't until I had the build completed that I realized my Razer Tiamat 7.1 headset doesn't work properly, because the mobo is missing the blue "side surround" jacks. Realtek Audio Console doesn't seem to be able to remap Line-in to Side Surround, either. Why would they exclude this feature from a mid-tier gaming mobo?? Is there a way to fix this issue without purchasing a dedicated sound card?