Recently I hooked up my PC to my home theater system via a DVI to HMDI cable for the Video, and an optical cable for the audio. So far it works great for things like Netflix, Pandora, and the like in stereo, but I was expecting to get 5.1 surround sound for gaming. I'm not. The audio is an on-board Realtek system on my Abit IP35-Pro motherboard. It is capable of 7.1. I double checked my BIOS setting and HD audio is enabled. I can get 5.1 audio from a DVD. The first game I tried was COD4. In the audio settings there is a setting for 5.1 audio, but after enabling it I only get 2.0. Even after restarting the game with 5.1 enabled I only get a stereo output. Any ideas? The only thing that I can think of is the game only does 5.1 through the speaker outputs and not the SPDIF (optical) output. Either that or I need an actual sound card to achieve what I want. Any insight would be helpful. Thanks!