dthec, which version of ltools are you using? I chose to use 1.7.5 cause I haven't read much issues with it besides the video going green. On the other hand of the 1.8, some people had problems and some had no problems. It's kind of 50/50 when using that one.
I just finished doing a friends box with the 1.7.5 and his xbox was only a few months old. I didn't encounter any problems with that one either.