I received mine yesterday and, like others reported here, there was no sound coming from the left side. Tried switching cables around, and still only sound from the right side, no sound from the left side. Sometimes after tapping the left earcup from the outside I can get sound out of it, but then it goes away again.
Reported this to Massdrop, and they referred me to HIFIMAN for a warranty claim. Both Massdrop and HIFIMAN customer service replied to me within just a few hours.
ftavaresJust to follow-up on this, I followed the instructions from HIFIMAN to send the faulty headphones to them. They gave me a UK address which was nice because it kept the shipping costs for me to a minimum. And this week I received new replacement headphones. The new headphones have a serial number in the 5xxx range, and seem to be working fine. The original faulty ones had a serial number in the 28xx range.
I didn't receive any compensation gift like others reported, and did have to cover the costs of shipping the faulty headphones (with tracking) back to them. But overall I'm happy with the experience. HIFIMAN were always very fast to reply to my emails, and did send me new headphones that are working. So happy customer after all.
Reported this to Massdrop, and they referred me to HIFIMAN for a warranty claim. Both Massdrop and HIFIMAN customer service replied to me within just a few hours.