Blu-ray disc rot on a few titles

Has anyone else been hit by blu-ray disc rot? I've just discovered it in my The Prestige blu-ray disc. I've only watched it once, on the PS3, about 1.5 months ago. Couple of days ago, I tried it again and realised that the PS3 wasn't able to read it. The surface of the disc looks like it has lots of blotches or specks, but when you run your fingers over the surface, its smooth, which means that the problem is happending below the top surface layer.