Off-white whine
To be fair, off-coloring could be a sign of bigger problems, at least when it comes to the cord. I’ve gone through two chargers, the first of which nearly caught on fire (I saw wisps of smoke and unplugged the charger immediately), the second of which had a cord that turned severely yellow for reasons unknown. I brought it to an Apple store just last week and the guy at the Genius Bar said, “Yeah, that’s totally unprecedented,” and he gave me a new charger because who knows what would have happened had I continued to use the other one, which was also a replacement charger, might I add.