you must have gotten a bad pair because I use mine quite often and they have held up very well. hope you get that resolved. there's no excuse for not replying to your emails.

@xsuper where did you buy it from?  Why not contacting the seller?  A lot of warranty claims with chinese headphones are handled through a seller, this way manufacturer only deals with authorized dealers to honor the warranty.  What I would recommend, regardless of who is your seller, contact Penon Audio (http://penonaudio.com/ - penonaudio@hotmail.com) and ask them if they can help you.  They are an authorized seller of a lot of headphones.  Perhaps, you can just pay shipping to send it to them and they will arrange a replacement unit for you.  Give it a shot, they helped a lot of Head-fi, even those who didn't buy products from them!

I'm sorry for your experience.
 
I have both the kc06 and the kc06a for a long time, and they seem very well built to me, and have held up very nicely. In fact, I fall asleep listening to the kc06a's every night, and they have withstood that abuse for a long time (where others have failed).