Having trouble getting audio working on your HDMI monitor? Using a DVI converter cable and an audio jack?

Some monitors will not output sound from the RCA or other audio source if the video is coming in with a HDMI/DVI conversion going on. If you are using a HDMI to DVI converter cable, you may have noticed that DVI can not carry audio.

Your monitor sends a couple blocks of binary information to your computer, known as EDID. This information tells your computer that the screen can play audio through the HDMI connection. The audio capabilities pass through a HDMI/DVI converter cable untouched while the actual audio gets clipped.

A solution to this problem is to pass fake EDID information to your video driver to make it appear that the monitor has no audio support.

By popular request, I've updated edid_disable_exts to have this function.
./edid_disable_exts --to-dvi original.bin fixed.bin

For nVidia cards the method is as follows:

1.) Download edid_disable_exts
2.) Run nvidia-settings, click on DFP-0, then click "Acquire EDID..."
3.) Run edid_disable_exts --to-dvi edid.bin edid-as-dvi.bin to generate a new edid.
4.) Update your xorg.conf to include the CustomEDID option in the device section.

Section "Device"
Identifier "nVidia"
Driver "nvidia"
Option "CustomEDID" "DFP-0:/etc/X11/edid-as-dvi.bin"
EndSection