White Screen won't go away?

I know this is a fairly common problem with this model of iPod since i've been working on them for the past year, however, this time out of the 70 or 80 that I've done I cannot get it to stop white screening. The ports are fine, I have shorted the board between the battery flex and the home button contact, I've desoldered the battery so it can reboot because it isn't allowing me to. I've tried another screen as well. None of this has done anything and I'm kinda out of ideas as far as what to do. I find it funny how I had the same issue on an iPod I finished yesterday and it took a mere two minutes lol. Regardless I would really like your input if you have some experience with this issue to the extent in which I do. Thanks!