That lamp area and connector can degrade with heat and time. There's also a note about not touching the lamp with your bare hand when installing and another note about power off then pull it out and plug it back in (that's a hint the connector/socket is aging.)
This may not answer your questions but I thought I would share this.
I have a Samsung DLP TV Model HL50A650C1F, The first lamp lasted almost 2 years, when it died the picture went off and all three lights started blinking. According to the manual this meant the Lamp was bad. I ordered a new one from Samsung Parts on 8/20/2010. I installed it about a week later when it arrived and it has worked great until 11/5/2010, same thing happened lost picture and three lights started blinking again. After about a week trying to get something from Samsung Parts about the warranty, they tell me today that because the Lamp wasn't blackened it was good and I would need to get the TV tested, I tried to explain to them that the first Lamp wasn't blackened either abd when I replaced it the TV worked fine. Does any of this make any sense? Any help ?