Hi all, I seem to have a light 'splodge' near the middle of the screen, around 1 foot square (on a 6 foot screen). It is most noticeable when projecting a purple background, as a lighter purple area. On a red, green or blue background it cannot be seen at all. I'm dismantled the projector and cleaned it of dust (as explained in this forum) but it didn't help - infact I now have a few 'dust' spots - oh well always a risk. Any idea what this light spot could be? Impending lamp failure? Lamp use shows 415 hours on Eco, none on full. Any advise appreciated.