I installed a new motherboard and processor but am using the same AMD Radeon graphics card I had. It was working fine but now there is no audio through the HDMI. I also reinstalled Windows 7 64-bit. The latest driver for the graphics card is installed, the HDMI output is set as the default sound source. I have tried both enabling and disabling the internal audio on the processor (Intel i5) in the BIOS, but neither works. Any ideas?