SAHARA ghosting

I have a SAHARA AV-600 SB LCD projector that has a big ghosting problem. dark images are displayed with a distinct shadow. The projector is about 3 years old and will be written off as soon as I can prove that it would cost more to mend than to buy a new projector. I assume this ghosting just happens as the thing gets old as we have replaced the lamp recently which didn't have any effect.
What causes this ghosting and how much would it be to rectify/is there any way of rectifing this?
Thanks