Long time reader of this thread, first time poster. Lots of great information here, this website is wonderful.
I took delivery of a HLT5687SX/XAA mid October. I immediately noticed the halo prism with dark scenes, espeicially watching DVD with letterbox. It looks like the issue has been solved by others with having the "diffuser kit" installed, by replacing the shiny ring with a black one.
Samsung tech just left, and he is going to actually replace the whole light engine assembly. I told him about just getting the "diffuser kit" and to just replace the ring, but he is insistant on getting a new assembly and just replacing it as a whole unit. Supposedly the new light engine will already have the black ring installed. He said we could just take a black marker tonight and paint it, but it would eventually have the same issue as he said the light assembly gets very hot.
So, they will be calling me once they get the new light engine. If I can get this fixed, I will be very happy with the set. I do have the latest firmware, as the TV shipped with it.
Also, 2 Samsung techs were over. one of them had to go to the bathroom, but I only have one bathroom. My wife was in the shower, he went outside for about 3 minutes and came back inside. My wife was out of the shower and I asked him if he needed to use the restroom, and he said no with a smirk on his face??? Did he piss in a bottle in the Samsung van or on my flowers? You make the decision LOL