If you want to take full advantage of your PC’s audio potential, you should connect your rig to your A/V receiver and passive speakers—or a really good set of powered speakers.

I have spliter but my PC recognize that Sony PJ *04 projector is connected to PC so it's only give 2.0 support. I don't know can i and how to force Windows 10 to send 5.1 sound because of it.