Oh my...I doesn't look good for the latest Pioneer flagship. The SE Master 1 has a pretty significant spike at 6kHz, but more worrying to me is the amount of ringing I see and hear. I'd characterize these as "zingy". I didn't hear the distortion in the bass, mostly because I wanted to stop listening. Zing!
Read more at http://www.innerfidelity.com/content/innerfidelity-update-january-2016#X2RILEATVKEHhBHA.99
Yeah I'll be contacting pioneer. I just got these a month ago in akihabara yodobashi. I asked at rmaf pioneer booth and he said try contracting pioneer support if they are able to help. He said they might not be able to since they were purchased in Japan.
If the pin is on the cable, why not try a replacement cable and see if it works. I had a similar issue but it had to do with the connector inside the HPs. Swap the left side of the cable with the right and see if the left side has sound. That should tell you whether its the cable or the HPs.