Thirty years ago, the ads in the hi-fi magazines said that Compact Discs offered “perfect sound forever.” “Perfect sound” is a complicated topic, but it’s apparent that “forever” isn’t happening. NPR has this piece on CD deterioration.
Some CD players do a better job than others at handling marginal discs, as I demonstrated in this post. It seems that the gold discs manufactured by defunct specialty labels like Mobile Fidelity and DCC are superior after all.
On the subject of “perfect sound,” I have come around to accepting that the CD format is as good as 2-channel audio gets. 44,100 samples per second, 16 bits per sample, represents the limit of what the human ear can hear. There are plenty of things that can be done wrong, and were wrong for a long time, with digital-to-analog conversion in CD players, but the bit depth and sampling rate are fine. Here is the best explanation I’ve seen.