From about the first 10 minutes I had the HP50s on my head I started noticing the mechanical sounds from the body of these headphones. Creak. Thunk. Click. Pop. It's awful and makes me cringe anticipating them.
I tried holding the cups still with my fingers and that helped, so I wedged some cardboard strips between the band and the cups as s temporary fix. This helped, but it didn't fix it. I did some research in this thread and found a lot of people talking about the sounds. But locating specific directions for fixing them were difficult. So I'm going to link to several posts here.
Here are some quick disassembly instructions:
Here's a post with a picture of where to apply blue tack to help remove the creaking:
I've taken mine apart twice now. The first time I didn't have any blue tack and I just tightened the screws on the hinge pieces. As reported by another forum member, they were LOOSE! Like not even finger tight. I think they took 5 or more turns each until they were snug. This seemed to help a lot at first, but with more listening time, the creaking was definitely still there.
I cracked them open again after going to Office Depot and buying a package of Scotch Removable Mounting Putty. As near as I can tell, this is very similar to Blue Tack (which I've never used or seen in person). It's a non-tacky putty that sticks to clean surfaces, but also pulls off fairly easily. I made balls of this a little bigger than a green pea and applied them to the lower part of the hinge as shown in the picture in the post above. This fills out inside of the shell and required more pressing to get the cups to go back together. It doesn't require much force. Just a bit as the putty compresses and conforms to shape.
Screwing the cups back together, they *definitely* feel more solid. The creaking is dramatically reduced. It's *almost* completely gone. I still have a pop or thunk every 5 to 10 minutes on the Left side cup only. I thought I had narrowed it down to the rotating metal area (the part that lets the cups twist for flat storage). I applied some oil here and wiped it off, but it doesn't seem to have completely cured the creaking. It's REALLY annoying.
The clamping force of these phones is pretty high. They are moderately uncomfortable. I would *swear* they got better after the putty application. But they still hurt my ears after an hour or two. Not bad. But not super comfortable like the SoundMagic HP150s were.
If I can *only* figure out the creaking problem, I think I'll be 98% satisfied. These phones sound So SWEET. But anticipating the thunk and pop sounds are starting to ruin my enjoyment some.