'forgot to add this: I've had a London CD since 1984 (when I purchased my first CD player) of Tchaikovsky's 1st and 3rd Piano Concertos. No CD (or SACD) player I've ever owned has been able to play the last few minutes of the 3rd without skipping all over the place. After applying L'Art du Son, the disc played perfectly - for the first time in 26 years!