This is likely caused by a build-up of foreign material on the chrome rails and/or wheels. The problem may be fixed by cleaning the chrome rails and wheels. To do so, wipe down the chrome rails and each wheel with a dry cloth. If needed, use a mild soapy solution to remove excessive build up, then wipe with a dry cloth.
DO NOT use WD-40 or silicone spray. Use of such products will invalidate your product warranty.