The same thing happened when I first used an iPhone X, and the random crackling/popping sound persisted for a long time until Apple issued a software update. T

The same thing happened when I first used an iPhone X, and the random crackling/popping sound persisted for a long time until Apple issued a software update. Though, it seemed to happen primarily with my own produced sounds and music, which I aggressively edited to back away to lower volume in the meantime. This helped a lot but the occasional pop or scratch never really went away until they changed the OS, and I haven’t seen it since. My theory is that if a sound has a high enough volume all by itself, it doesn’t “mix” well with a lot of other sounds that have sufficiently high volume. And with music, unless each of the instrument tracks has a moderate volume, an overlap of enough notes with high volume could go off the top and be clipped, producing a horrible scratch. It could be as simple as speakers that support a better frequency range. Perhaps something used to be done in software that is now done with higher-quality audio hardware, allowing imperfections to come through that were not noticeable before. I remember firing up old games with better speakers for instance, and being shocked at how flawed their sound really was; better equipment just didn’t exist when the games were made so they didn’t edit past the perceptible range of the audio equipment of the time. Sometimes you really do need to experience sound with the equipment that existed when it was produced.