I have a pair of HD668B that I modded some. Mods: Added electrical table inside the cups covering the holes. This lowers the sound stage but not too much and helps control the sound. Removed paper inserts in the cups because not needed with 1st mod Removed foam inserts. Clears up the sound...

So after jerking the extension jack out one too many times, using an extension that was way too big and heavy, etc, I damaged the plug and needed to repair it. I followed how it already was when I first did it, but I didn't do a good enough job. Now I'm trying to do it again but can't remember...