I have a PC hooked to my home receiver which is a Pioneer VSX-1123, and I'm using the HDMI output from my video card to transmit the audio and video to it. However for a reason I can not figure out at times I can't get any audio and the VSX-1123 does not show up in the audio device list on the PC, and other times it works perfectly, the VSX-1123 shows up in windows as an audio device. I've tried replacing the HDMI cable but I'm still having the problem, but it is only with audio, video always works fine. I'm thinking maybe transmitting the audio over another type of cable might be a better choice. I have a free optical input on the receiver that I can assign to the PC input, so what would I need to buy to get the audio from the PC to the optical input of the receiver? The built in sound card on the motherboard does have an optical output labeled SPIDF but I can't figure out how to assign the audio out of this port. Any help or suggestions would be really appreciated.