I've suddenly started experiencing distorted graphics on my XBox 360. It only seems to happen for the 3d graphics, the startup logo screen has the problem, and my avatar, and the graphics within games is broken now too - just played Call Of Duty 4, and there's uneven black vertical stripes in there. I've noticed lots of blue dots too. The 2d stuff all seems to still appear perfect in the dashboard. Is my XBox broken?!