Sony has said that it will replace a number of DVDs that caused problems for many of its customers. 20 DVD titles were affected by the glitch—including the movies Casino Royal, Rocky Balboa, and Stranger Than Fiction—which was caused by Sony's ARccOS copy protection on the discs. ARccOS is a secondary level of DRM on Sony's DVDs, used in conjunction with another form of copy protection, the well-known Content Scramble System (CSS). ARccOS intentionally introduces errors to certain sectors of the DVD so that ripping software that reads the disc sequentially will generate errors in the ripped product. Most set-top DVD players can read instructions on the disc to skip over these intentional errors, though, which then produces the expected video output for most users. Others cannot. Although the company has been using ARccOS on its DVDs for some time now, a recent update to the copy protection scheme caused the DVDs to be incompatible with what Sony describes as "a very small number" of DVD players. The issue came to light when a discussion began on Amazon.com's forums about Stranger Than Fiction, which blossomed into the discovery that a handful of Sony DVDs were not working for some customers. The company eventually confirmed to one customer that the incompatibility issue was due to an ARccOS update. The company advised him to update the firmware on his Sony DVD player at that time, with a firmware update that the company had not yet released. Sony has apparently decided to tweak its ARccOS software once again in an attempt to fix the problem. Sony claimed in its statement that they only received a miniscule number of complaints "on less than one-thousandth of one percent of affected discs shipped," and said that the update has solved all compatibility issues. This is another example of Sony continuing to fumble with DRM on its media. The DVD compatibility glitch comes only a few months after Sony finally settled with the FTC over the rootkit mess that it had created in order to "protect" its CDs from unauthorized use on PCs. After quietly installing software on customers' computers—software that turned out to be near impossible to uninstall and easily exploitable by hackers—the lawsuits started piling on. The company eventually agreed to replace customers' CDs as well as pay up to $150 to anyone who spent money trying to get rid of the rootkit. It looks like Sony decided to head the lawsuits off at the pass this time by fixing the DVDs' protection software before too many discs got out, but the company will still have to swallow some costs for the flub. If you're affected by Sony's latest DRM misstep, you can contact their customer service department at 800-860-2878.