I see HDMI audio in settings, but no sound comes out

Hi there,

I just installed Yosemite on my pc and everything is working, apart from HDMI audio. In settings I see 2 HDMI outputs but when I tried them both nothing happened. I have installed a kext called HDMI audio for AMD or NVIDIA but it didn't work (It has worked in the past). Audio has been playing because the headphone jack works but when I switch nothing happens. Any Ideas