Solved! help with 5.1 surround over optical

[brandxbeer]

I have 2 1070 in sli. I'm playing on a sony bravia 55xbr 4k tv. I can use my receiver as it's not 4k compatible (pioneer vsx 520). I had an hdmi cable going from my pc to my tv, then an optical to my receiver. The sound worked ok, but the rear speakers are not working properly when I try the nvidia control panel test for surround (The rear speaker test plays in the fronts instead.)
I then tried hooking up the sound with an optical cable from my mobo (gigabyte x97-udh3). I cannot get any sound now. I went through all my available devices in my playback devices and none of them produce any sound.
Any help is greatly appreciated.

 

[sidfrgaming]

The optical cable is not capable of carrying 5.1 surround (probably)
It is only used to transmit dolby digital audio which is commonly 2ch
If u have Dolby pro logic in ur av receiver use it to upscale the 2ch digital audio to 5.1 surround

 

[sidfrgaming]

Most games have dolby digital
Pro logic upscales it to 5.1 surround