xorg.conf resets

[elightbo]

I am running knoppmyth and trying to configure the graphics card for a new-to-me HDTV. However, whenever I make a change to the xorg.conf file and reboot, the file is returned to the state before I edited it.

One comment used more than once in the file is the line...
# Auto-generated by KNOPPIX mkxf86config
However, I cannot fine the mkxf86config file anywhere on my system. How do I prevent the file from being reset?

Thanks in advance for the help