ive had this player for several years (at least 4-5) and although i try to keep it closed at all times, i am now getting an error message occasionally saying to clean the disk when trying to watch a movie in the player. when i look at the disc, it does appear a little dusty. I dust it off but if i put it back in, it gets dusty again. this doesnt happen all the time but often enough that it is annoying. i also find the player skipping or stopping more now a days then ever before on mulitple different discs. what is the recommended way to clean this thing?

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