Be mindful that the underside is the readable surface, and that scratches can cause uncorrectable errors. The top side of recordable Cds is sensitive to certain types of marking pens. John Kilgore in the Masque NY Studio has extensive knowledge of the do's and don't's concerning recordable CDs. Available from the technical dept. The AMC-9 is a handy device that will dust off your CD player's lens safely and effectively.
Canned air is also helpful for blowing off accumulated dust inside the slot on CD cart machines.
After a fair amount of testing and research, the following information has been discovered. Probably happens on disc insertion, but exact failure path is unknown. Since this has never happened with Denon machines, and 4 Sonys have failed with 4 different operators, we must assume it is some design flaw on Sony's part. In response to the many requests of our clients for a solution for driving the outputs of unbalanced, or poorly balanced equipment over long lines, Masque has developed a couple of new devices. For the longest time many of our clients have been using Sescom's IL-19 for this application.