1999 Toyota Corolla Owners Manual - Page 118

C orolla (U) CAUTION Compact disc players use invisible laser beam which could cause hazardous radiation exposure if directed outside the unit. Be sure to operate the player correctly as instructed. A new disc may have rough edges on its inner and outer perimeter. Remove the rough edges by pressing the side of a ball- point pen or pencil against the inner and outer perimeter of the disc as shown. If you continue to play a disc with rough edges, flakes will fall on to the signal side of the disc and cause sound skipping or other problems. 118