I recently sent in my HE560 in to the HIFIMAN US service department under warranty and I received a replacement pair, however the left slider for the headband adjustment is very loose. The right headband slider is tight, as it should be, and never moves, but the left slider moves out of place while I'm wearing the headphones. I tried to ignore the issue, but constantly having to readjust the headband slider is very bothersome. I believe I received a defective replacement and when I spoke to email@example.com I was told I must ship the headphones to China this time for a replacement because the US service department is out of replacement stock, but shipping to China to exchange a replacement pair which shouldn't have had any issues is considerably more expensive than what I paid to return the headphones the first time. Is there any other way to resolve this problem? Thank you EDIT: Talked with HIFIMAN and we decided that they would send me a replacement headband and I can install it myself which I think is a fair compromise. Thanks HIFIMAN.