Quoted from Frax:
It's just a part of LED dmd's unfortunately. Since it's a grid of blocks, even small things out of a very tight tolerance will lead to misalignment of the dot grid and leave gaps like this. You could contact Stern or your distrib and see if they feel like replacing it, but it shouldn't change over time.
The only reason I'd be concerned is that you said it didn't look like that at first....not sure what would cause the blocks to move. I'd personally go out on a limb and chalk it up to "ignorance by virtue of exitement" . I'd bet it was there all along and you just got a chance to notice it.
Your right when your unboxing and excited small things don't jump out at you, just checked unboxing video and it was there when first turned on(I know sad I videoed unboxing lol) so if they don't get worse I can live with it thanks guys for help.