Calls work for 30 seconds then go silent. NAT issue?
Classic NAT keepalive issue, RTP stream is closed by the router.
Try this first
- 1Set SIP keepalive to 15 or 30 seconds
- 2Configure SBC or softphone with STUN server (e.g. stun.l.google.com)
- 3TURN needed for symmetric NAT, otherwise RTP gets stuck
- 4Disable ALG (SIP helper) on router, it usually breaks things
When to bring us in
One-way audio after 30 sec? NAT binding expires, fix on the SBC.
See also
- Voys, BelXS or RoutIT, which cloud PBX fits?Three popular NL platforms, differences are admin UI, partner model and per-user price.
- Teams Phone: Calling Plan, Direct Routing or Operator Connect?Three ways to connect PSTN to Teams, cost and management differ a lot.
- 3CX: self-host on VPS or take 3CX cloud?Self-host saves licence, but you own SBC, backup and updates.
None of the above fits?
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