why do cd players "sometimes" not read a disc?

My Lexicon RT-20 is sometimes refusing to read a disc that has just been playing?

ptss09-20-2013 3:55am

jafant Details Discussions Posts This discussion Message User 18,802 posts 09-21-2013 at 05:38pm Copy Comment URL Report Comment Edit Delete The RT 20 is a killer player. I would consider a 'tune up' if it is older than 5 years.