Hi everyone,
 
I have an older pair of Sharper Image headphones (I know some of you are cringing) which only has the left ear working. I've repaired headphones before that only have one ear working, but this one seems different because although there are some loose wires at the plug, the actual noise cancelling functionality isn't working on the right cup. When I flick it on, I hear it activate on the left, but the right is stone cold silent. I pulled it apart to see if I could find any loose wires, but everything seems to be fitting snugly.
 
Also, the plug wires are permanently attached to the cups - that is, they are not removable. Any ideas on what could be going wrong?