Blackberry maker Research In Motion (RIM) said Monday it is recalling around 1,000 PlayBook tablet computers because of an operating system issue. The Waterloo, Ontario-based company said most of the affected devices were still in the distribution channel and had not reached customers. RIM said the affected PlayBooks may not be able to properly load software upon initial set-up. \"RIM is working to replace the affected devices,\" it said in a statement. \"In the small number of cases where a customer received a PlayBook that is unable to properly load software upon initial set-up, they can contact RIM for assistance,\" the company added. According to technology blog Engadget, the faulty PlayBooks were shipped to US office supply giant Staples. RIM shares were down 1.30 percent at $42.68 in pre-market trading. RIM released the PlayBook in April to mixed reviews. The device is RIM\'s answer to Apple\'s hot-selling iPad and its first foray outside the mobile phone realm. RIM is offering three models of the PlayBook. A version with 16 gigabytes of storage for $499, a 32GB model for $599 and one with 64GB for $699. The prices are the same as for comparable models of the iPad. RIM describes the PlayBook as the first \"professional-grade\" tablet and has stressed its integration with its BlackBerry smartphone, a favorite among business users. The PlayBook has a seven-inch (17.8-centimeter) touchscreen, smaller than the iPad\'s 9.7 inches (24.7-cm) and at less than a pound (425 grams), the PlayBook is lighter than the iPad 2\'s 1.3 pounds (590 grams).