I just have to jump in here, and note that I've had horrible experiences with the 4H. I've owned two, and both have been thrown in the trash for the exact same reason.
After a while, the sound will cut in and out, and I believe it to be due to poor wiring, because if you hold it a certain way with your hand, it sometimes improves the situation.
The headphones have decent sound quality, but since I've had two pairs die the same way, I'd highly recommend staying away from these. Unless of course, you want to use it for a week only.