A little more info please. Are you connected to a PS3 or a PC?
The headphones I found on Tritton's site are wired. Is that true of yours? Does the station stay if you use other headphones?
It not unheard of to faintly hear a radio station through headphones. All that is required to pick up radio waves is really a piece of wire (antenna) and a signal detector (anything electronic). Most equipment has filters to limit it, but you may be close to a radio station. Can you identify the station, and see where they are?
In any case, you may be stuck, but there are a couple of things you can try. First , just unplug the optical cable, but leave the USB. If the radio stops, the problem is likely inside the PS3.
If you have the 7.1 'phones, the manual indicates a USB cable. I think that is only used for power. Do you have a PC close to plug it into, or even a phone charger. (in fact, you could just move the decoder box to the PC, it doesn't need the optical cable connected for this test).
I'll give it some more thought and get back to you if i think of anything.