Brand new projector; spots on the screen

Hello I just bought a benq W710ST and I've noticed it's putting these two fist sized circles near the top two corners almost like a lense flair or water spot. These are not on the out side of the lense as I have cleaned it with no results, if i turn the focus ring the spots will mostly hold their position but change size. I think it's some internal smudge on the lense or something should I be worried about this, should I send it back on warrantee, have you ever experienced this before?