Recently purchased a Samsung PN50A550 50" Plasma and was experiencing a white line suddenly popping up on the left edge of the screen when using my Xbox360 via VGA cable. Used Samsung's "auto correction" PC display synch feature and have pressed the "P.Button" to change picture size, only to have it disappear temporarily, and then reappear minutes later. I tried shifting/adjusting the picture, but no luck. I also experienced the white edge line appearing at the top of the screen simultaneously with the lefthand edge, and sometimes a white edge line at the bottom of the screen by itself. The console is set to the Plasma's native resolution of 1920 x 1080 and "Enhanced". Swapped VGA cable for composite, and did not experience this problem. Only shows up in gameplay or HD DVD usage, and not the Xbox console home screen.