Does GW2 output 7.1 or 5.1?
I run a Yamaha 5.1 surround via HDMI from my R9 270x and I get accurate surround. It is mostly controlled through the windows configuration. I will say that through my old Sound Blaster Recon 3D it was not as good, so it may be that my Yamaha system can distribute the sound better than my old 5.1 PC speakers could.
i have 2.1 with virtual surround but it sounds like 5.1, i think 7.1 is supported but i am at least sure 5.1 works.
I have a 7.1 virtual surround headphone and it seems to work over there.