Changelog

11.0.0 is headlined by a foundational change to the media path: jambonz no longer runs on FreeSWITCH. In its place is mediajam, a purpose-built media server written in Go that the feature-server drives directly. mediajam is designed to scale to far more concurrent sessions per server than FreeSWITCH, to scale linearly on large multi-core machines, and to run with a much smaller footprint — it’s available on both amd and arm64 and as a minimal Docker image, with no SIP stack and no per-channel sockets. It handles audio (PCMU/PCMA/Opus/G.722 + telephone-event) over RTP with symmetric latching, RFC 2833 DTMF, file/HTTP/tone/silence playback, bridging, conferencing, and hosts the Krisp noise-isolation and turn-taking engines (separate license required from Krisp when self hosting). This is the biggest architectural change in the platform’s history and is the reason 11.0.0 is a major-version bump. For further details on the media server, including benchmarks please check out our blog here.

On top of the new media server, 11.0.0 adds a transfer verb that packages the common transfer choreographies (blind, and warm parked / three-way) into a single declarative verb with built-in briefing, confirmation, and failure handling — and exposes the same capability to the agent and llm verbs through a declarative handoff block that transfers the caller to a human when the model asks for it. Both AI verbs also gain a built-in hangup tool that lets the model end the call on its own. Conferences become observable and controllable from the API, the speech-vendor lineup is refreshed (with several legacy vendors removed), and the SBCs get accuracy fixes around live call counts plus a round of cross-account authorization hardening in the API server.

Media server

1. mediajam replaces FreeSWITCH — The feature-server media path now runs on the new Go-based mediajam media server instead of FreeSWITCH. Higher session density, linear multi-core scaling, and a small footprint that builds on any Linux distro and as a minimal Docker image. Audio-only (PCMU/PCMA + telephone-event), RTP via Pion, RFC 2833 DTMF, resampling via libspeexdsp, with Krisp and RNNoise available for noise isolation and turn-taking.

New Features & Improvements

1. Transfer verb — New transfer verb that hands a call off to another destination as a blind transfer (SIP REFER or bridged dial) or a warm transfer (caller parked on hold, or joined into a three-way conference), with spoken briefs, confirmation gates, hold music, and a configurable disposition (return to the app, go to voicemail, or hang up) when the transfer does not complete.
2. Transfer-to-human handoff for AI verbs — The agent and llm verbs accept a declarative handoff block. When present, the runtime injects a transfer_to_human tool into the model’s toolset and runs the packaged transfer choreography when the model calls it — no toolHook required.
3. Built-in hangup tool for AI verbs — The agent and llm verbs accept a hangup block that injects a hangup tool the model can call to end the call on its own, with an optional reason placed in the X-Reason header on the outbound BYE.
4. Conference observability & control (API) — GET /Accounts/{sid}/Conferences?expand=participants returns live conference rooms with their participants and durations; new POST/DELETE /Accounts/{sid}/Conferences/{name}/listen endpoints start and stop a conference-scoped listen fork, addressed by conference name with no participant leg.
5. Bidirectional conference listen stream — The conference listen fork is bidirectional: the room’s mixed audio streams to your WebSocket endpoint, and audio the WebSocket server streams back is mixed into the room and heard by every participant (unless disabled with disableBidirectionalAudio).
6. Play or speak to a whole room — The media server can play an audio file (or tone) and speak TTS to an entire conference/room, mixed into the room mix so all participants hear it, with the ability to stop an in-flight playout.
7. Live Call Control — transfer — updateCall now accepts transfer as a live call control operation.
8. New speech vendors and models — Added support for xAI (STT), Murf (STT and TTS), Rime coda, Cartesia Sonic 3.5 (with word timestamps), Soniox v5 real-time model (stt-rt-v5), and NVIDIA Riva cloud (NVCF) credentials with refreshed Magpie voices. The webapp exposes the new vendors in the speech-services UI.
9. Speech vendors removed — Verbio, Cobalt, Nuance, Voxist, and PlayHT have been deprecated and removed across the feature-server, API server, and webapp.
10. gather interim events — Interim gather events now include a verb_id.
11. API security hardening — Added cross-account authorization checks (CWE-639) across API server resources (tenants, LCR carrier-set entries, SIP/SMPP gateways, custom voices, and more) to prevent access to records outside the caller’s scope.
12. SBC gateway safety — Carrier configuration now rejects 0.0.0.0 and /0 gateways, and sbc_addresses enforces a unique host:port index.

Bug Fixes

• Call counts on transfer/abandon — A call transferred off a feature-server now correctly decrements the SBC call count (inbound and outbound), and abandoned outbound calls decrement the count as well. Long-running calls are no longer reaped by the cleanup cron (the debug:incalls keys for active calls are refreshed).
• Krisp/noise alerts — Alerts raised when Krisp noise isolation or turn detection fails now report the real vendor and underlying error instead of a hardcoded message.
• Conference timeLimit — timeLimit is now preserved on a transferred feature-server when joining a conference.
• Speech-to-speech teardown — The call now ends cleanly when an s2s session ends with no follow-on verbs; ElevenLabs s2s coerces non-string client_tool_result.result values to strings; and s2s disconnect logging no longer mislabels _onDisconnect as _onConnectFailure.
• listen verb — Fixed the listen verb being torn down (with the wrong handler) when a background listen task failed.
• dial verb — An unanswered actionHook is no longer logged as a dial error.
• Scale-in — Resource teardown in _clearResources is now bounded so scale-in can’t hang.
• Security/logging — The carrier register_password is no longer written to the log.