The several backups I've made, on Krayzie's softmod, gives a DDE consistently after the "loading" bar fills at the main menu. It doesn't make any noise like it's actually having trouble reading the disc, it just abruptly says "The disk you are using is dirty or damaged etc" and stops spinning. If I manually boot the multiplayer XBE file, it works fine, but I have no desire to play multiplayer.
An odd thing that occurred to me: since Double Agent was, essentially, the last decent xbox game ever made, could it have a novel type of copy protection that either identifies the existence of a Krayzie softmod or DVD+R media?
I have the iso on my laptop and haven't actually put in the original since installing Krayzie, so I haven't yet tested the former hypothesis.
THANKS BROS <3 <3 no homo tho