Razer BlackShark V2 review?

Hey everyone! I just picked up some new headphones for my son, but I’m hitting a massive wall here. Does anyone know how to tweak the settings so the laptop actually uses the headset mic instead of the built-in one? They're plugged in via a single 3.5mm jack. Honestly, it's a total nightmare.

Finally got it sorted out with Best Buy. Looks like they pushed an "update" for the sound card drivers—some Realtek thing.