I've got a problem where incoming calls, using a DID number, do not always go through. Sometimes they do, but sometimes the calling party receives a 'fast busy' (reorder tone). I've tried using two different service providers (Vitelity and VoIP.ms) and this problem occurs with both. Vitelity technical support told me that they are receiving a "302 Moved Temporarily" message from me, when the calls don't go through. What should I look for to solve this problem? John Rayfield, Jr.