I know this is ancient subject but SIP on SBX seems to be a dead subject. Did your Windstream SIP trunks continue working on the SBX? Reason I ask is I'm having difficulty with NexVortex on SBX, that is keeping it running. For unexplained reasons the SIP trunks stop working and there is no reliable way to get them back up and running. Reset Comcast modem, system, VOIB. Re-enter IP on VOIB. Re-enter SIP2 table NexVortex registration information. Factory no help. What's your experience? [email protected]