Fun phase story: I get new headphones. Yay! I plug them in, I start listening to music. Something sounds... odd. I can't quite put my finger on it. Then I loa

Fun phase story: I get new headphones. Yay! I plug them in, I start listening to music. Something sounds... odd. I can't quite put my finger on it. Then I load up a track and notice that the vocals are missing. Completely. The backing track's there, but the singer isn't. I switch back to my old headphones. Yup, the singer's there. I call my cow orkers over to verify that I'm not simply going mad. I'm not; they hear it too. What was happening, we eventually discovered, was that I hadn't noticed that the headphones used a three-ring jack rather than an ordinary two-ring stereo jack, and when plugged in to a two-ring socket, the left and right channels were being shorted together. Because the singer was in the centre of the mix, his vocals were in opposite phases in the two channels, and were therefore cancelling out. The backing track was offset left and right from centre, and so weren't. Phase artifacts are weird.