3.Click Device Advanced Settings and select separate all input jacks as independent input devices.Click the document folder icon in Realtek HD Audio Manager, as below image and check both options,.1.Update your Realtek High definition Audio driver to the latest version.How do you use both audio jacks at the same time?
This is also pretty easy to do in Windows 10: How can we play sound in speakers and headphones at the same time in Windows 10?