I have or I used to have, before I sold it off to some friends who really like my old 73838, and after a bulb replacement or two along the way we have a new problem. After about 10 minutes it begins to what would best be described as going green and not the good way, before going gray-ish, and also not the good way. Any ideas to our new problem, no blinky lights to signal lamp failure or anything like that. Pulled the lamp looked good(it has only been in 3 months) but pulled a replacement we had in the closet and it does the same thing. So it's probably not the lamp, but the owner's manual I had is lone gone and I was wondering if there is a sequence to put it into some sort of diagnostic mode that it may point me in the right direction other than the colored lights that come on the front indicating the ones listed in the manual. Thanks.