Like Kelson, I have had -RAM disks that look perfect, even when examined using a magnifying glass, but would not work properly in my EH50. After a quick cleaning with mild soap and water, and drying with a lint-free cloth, they have all come back. Ironically, I have Maxell and Panasonic DVD-RAM disks, but the Maxells are 5x while the Panasonic ones are all 3x, so the Maxells get used a lot. I have had more problems with the Panasonic then the Maxell disks. I had two five packs of Pansonics very bad, right out of the box, but worked flawlessly many times after an initial cleaning. I now wash all my -RAMs when they are new, before the initial use. Someone here said that there is a lubricant used on the disk presses, and if there was too much applied, or if it wasn't completely removed in the fabrication process, it can interfere with the laser. So... I wash 'em and they work.