The song is the same length every time, but what it interrupts in your life keeps changing.

A song does not change and your life around it does. The same four minutes land in a car on a good morning, in a kitchen after bad news, in a room you no longer live in, and each time they interrupt something different. What you call the meaning of the song is largely the meaning of what it walked into.

This explains why old favourites can suddenly feel wrong, or newly unbearable, or better than they ever were. The change is not disloyalty on your part. If a piece of music has stopped working, let it rest rather than forcing it. And notice what you are playing during good stretches, because you are quietly building the thing that will bring them back later.