Hi Tulli, thank you very much for creating that file so quickly, it is much appreciated. Although DTS and Dolby Digital now appear in the "AMD HDMI Output" properties window on the HTPC, the TV unfortunately still does not pass it through. When I play a file with AC3 audio, there is no sound and the Dolby Digital option in the TV's sound properties is greyed out and cannot be selected. So, I've now hooked up the motherboard's optical audio out to the amplifier and I will have to introduce an audio delay to compensate for the TV's image processing time. This is what I wanted to avoid but I don't think I have another option. Anyway, thanks again for your assistance!