GPU Passtrough HDMI Sound

Hi guys

I am new to this hackintosh thing, but i managed to install HighSierra on my proxmox VE with clover and passed trough a 980ti with Inject NVIDIA in Clover.

I tried to passtrough a AMD 7770 but after the Apple logo the screen is shows only red pixels and is bad.

Now if i decide to stuck with the 980ti on HighSierra there is only one problem and that is sound

Is it possible to enable HDMI Sound in macOs with my GPU or do i need a USB Soundcard?

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LG thx for help