20 Most Recent ViewSonic PJ400 Multimedia Projector Questions & Answers

http://www.uaf.com/new-air-filter-product-announcements.aspx

OK, that explains it. The bulb you have installed in the projector might be the original bulb that came with the projecoter when it was new. Just becuase it states 334 hours does not mean it is new. In fact, you could have a original bulb with 3000 hrs and reset the hour timer on the projector, which means your 3000 hour bulb might have 3334 hours on it because the person who owned it before you, reset the hour timer.. Best bet, buy a new bulb and reset the hour meter and see what happens. If you have the same problem, then your ballest might needs to be replace which is rare...

Check if there is a cooling fan. Is it rotating? It is also possible that the filter is dusty and needs to be cleaned/replaced. (all projectors have a cooling fan and a filter to prevent dust from reaching the lamp. A faulty fan or a reduced air flow may cause an overheat problem)

Hello, It may be the DMD chip. Do you get the spots on the display even when there is no source connected? Are the spots multiplying? If so, then it is the DMD chip. If it is under warranty, then ship it back. Also, if the projector is less than 5 years old, you could get the chip replaced for free. Some DMD chips have a 5 year warranty that are still good even after the projector's warranty.