Sometimes my ser proxy resends an INVITE 67 milliseconds after the original INVITE without receiving any response from the recipient.  Essentially, what would normally be a 1 second timer for a resend is vastly shortened with no real explanation.  If there is a Trixbox at the other end, the conversation results in a dropped call as the Trixbox continues to send repeated 200 Oks, but does not acknowledge the ACKs to those messages.

The Asterix supposedly has a fix for this issue that is not included in the Trixbox.

What I am trying to determine, though, is WHY the double invites are sent in the first place.

Thanks,
Steve