[Disengager]

So, the story:
 
I was extremely impressed with the early previews of the HE-400's so I preordered a pair for $350. I got them and like most people, my left driver was faulty. So I shipped them to Head-Direct in New York for repair. 2 days later they announced the HE-500 upgrade program. So I paid another $15 to ship the box and accessory bag back also. Wait, waited, waited. Finally Wednesday my HE-500's showed up and even using a Fiio E7 I knew they were amazing. So today my Schiit Asgard shows up and I'm absolutely blown away. Like, I've never experienced music like that before. Except there's one little problem.....
 

 
It literally slid out of the connector. I have no clue how to fix this, I'm not savvy at all when it comes to fixing hardware. Can someone walk me through repairing this or direct me to a reasonably priced replacement (not upgrade, replacement) for this that I could have within 2-3 days tops?

 

[crimsonOkami]

What is that, an rf coaxial plug? you can verify this by seeing if you can plug it into the coaxail port in your tv.  well you're not going to be fixing it without a replacement jack, it's surprising that despite how popular rf plugs are it's hard to find a good replacement plug.
 
This should work if the plug shown in an rf plug, it might not be pretty or fancy but it'll work
http://www.markertek.com/Connectors-Adapters/Video-Connectors/RF-Connectors/TecNec-Cables-Connectors/F-MQWIK.xhtml
 
edit:
if you pull hard enough on the black plastic part does it come apart?

 

[Happy Camper]

Looks like you are twisting the cable to thread the connector to the headphone. Both cables show evidence of twisting. This is an easy fix for one with a solder iron. If you don't have one, take the cable to an audio store or radio shack.

In the mean time, the nut does thread separate of the connector, meaning you only turn the nut and not the whole body.