I bought the Sennheiser 558 a few days ago but I've noticed that it sometimes makes distorted sound when I connect it via the audio jack on my laptop. It's not a problem with a song or a video because even when I play games, sometimes the sound is distorted. I had no problem with Apple earphone at all so it's quite strange. The Sennheiser has a big audio jack (probably for amplifier?) but it also comes with a 3.5mm adapter so I'm not sure if this is the cause. I also noticed that when I plug the Sennheiser in my laptop, it's kinda flimsy and loose so this might be another reason. I bought a USB hub with audio jack on Amazon and tried plugging the Sennheiser in. It doesn't make distorted sound anymore, however, sometimes it sounds like a fraction of a second of the song is skipped and the song just fastforward. I don't know what this is called but hopefully you guys can understand what it is. I've also tried the headphone with my phone and it sounds just fine, no distorted sound or skipped anything. And all the distorted sound and skipped are random so it's not because of the song. I download foobar2000 and it seems it makes distorted sound and skips more often than with Windows media player for some reason.