My Voyager 520 BT headset's ear loop separated itself. So I got onto Plantronics website and chatted with their rep. I asked if this could be fixed with crazy glue or something. A fellow by the name of Matt said to just send it in and they'll send me back a brand new one. I got a replacement 520 overnighted to within four days.
No need for an RMA, all I did was printed out the conversation I had with Matt and included my name and address. Not only does Plantronic BT headsets rock, their support does too!