SIP PBX Media Actions

Overview

The Media resource controls playback, tones, recording, media waiting, and DTMF sending.

Operations

Operation	Purpose	Output branches
Play Audio	Play audio from binary, file, or HTTP.	Interrupted + Completed in blocking mode, Result in background mode
Play Tone	Generate daemon-owned tones.	Interrupted in infinite blocking tone, otherwise blocking/background branches
Record Audio	Record audio to binary, file, or HTTP.	Interrupted + Completed in blocking mode, Result in background mode
Stop Media	Stop media by mediaId or by leg.	Result
Wait Media	Wait for a media operation to finish or interrupt.	Interrupted, Timeout, Completed
Send DTMF	Send DTMF over a live leg.	Result

Common Leg Resolution

Most media actions resolve legId in this order:

1. explicit Options -> Leg ID
2. item.json.legId
3. item.json.sipPbx.legId

Stop Media and Wait Media can also resolve mediaId from the current item.

Common Media Options

Option	Applies to	Description
Leg ID	Most media start actions	Explicit target leg.
Stop Other Media	Playback and recording starts	Stop other active media on the same leg before starting this one.
Ducking Factor	Playback actions	Attenuates lower-priority concurrent playback.
Execution Mode	Playback and recording starts	Blocking waits for a terminal media event. Background returns immediately.
Interrupt On	Play Audio, Play Tone, Record Audio	Multi-select interrupt signals. Depending on the action, available values are DTMF, Voice, or Silence.

Operation: Play Audio

Parameters

Parameter	Required	Shown when	Description
Source Type	Yes	Always	Binary, File, or HTTP.
Binary Property	Yes	Source Type = Binary	Item binary property name.
File Path	Yes	Source Type = File	File path on the n8n host.
URL	Yes	Source Type = HTTP	HTTP or HTTPS audio source URL.
HTTP Auth	No	Source Type = HTTP	None, Predefined, or Generic.
Credential Type	Yes	HTTP Auth = Predefined	n8n credential used to sign the HTTP request.
Generic Auth Type	Yes	HTTP Auth = Generic	Generic auth credential used to sign the HTTP request.
Interrupt On	No	Always	Multi-select interrupt signals for playback. Available values: DTMF, Voice.

Options

Option	Shown when	Description
Leg ID	Always	Explicit target leg.
HTTP Method	Source Type = HTTP	GET, POST, or PUT.
HTTP Headers	Source Type = HTTP	Extra HTTP headers.
Voice Threshold	Interrupt On contains Voice	Voice activity threshold.
Voice Duration (ms)	Interrupt On contains Voice	Voice activity duration required to trigger interruption.
Stop Other Media	Always	Stop other active media on the same leg first.
Ducking Factor	Always	Concurrent playback ducking control.
Execution Mode	Always	Blocking or Background.

Output

Branch	When used	Typical fields
Result	Execution Mode = Background	mediaId, legId, optional sipPbx.mediaId, optional sipPbx.legId
Interrupted	Execution Mode = Blocking	mediaId, legId, interruptReason, optional digit
Completed	Execution Mode = Blocking	mediaId, legId

Operation: Play Tone

Parameters

Parameter	Required	Shown when	Description
Tone	Yes	Always	Built-in preset or Custom.
Custom Tone	Yes	Tone = Custom	Tone pattern syntax <freqs>/<durationMs>,....
Repeat Forever	No	Always	Infinite tone playback.
Interrupt On	No	Always	Multi-select interrupt signals for tone playback. Available values: DTMF, Voice.

Options

Option	Shown when	Description
Leg ID	Always	Explicit target leg.
Voice Threshold	Interrupt On contains Voice	Voice activity threshold.
Voice Duration (ms)	Interrupt On contains Voice	Voice activity duration required to trigger interruption.
Stop Other Media	Always	Stop other active media on the same leg first.
Ducking Factor	Always	Concurrent playback ducking control.
Execution Mode	Always	Blocking or Background.

Output

Branch	When used	Typical fields
Result	Execution Mode = Background	mediaId, legId
Interrupted	Execution Mode = Blocking	mediaId, legId, interruptReason, optional digit
Completed	Execution Mode = Blocking and finite tone	mediaId, legId

Operation: Record Audio

Parameters

Parameter	Required	Shown when	Description
Interrupt On	No	Always	Multi-select interrupt signals for recording. Available values: DTMF, Silence.
Max Duration (Seconds)	No	Always	Recording duration cap.
File Format	Yes	Always	WAV, MP3, Opus, or OGG.
Output Type	Yes	Always	Binary, File, or HTTP.
Binary Property	Yes	Output Type = Binary	Item binary property to write into.
File Path	Yes	Output Type = File	Output file path on the n8n host.
URL	Yes	Output Type = HTTP	Upload destination URL.
HTTP Auth	No	Output Type = HTTP	None, Predefined, or Generic.
Credential Type	Yes	HTTP Auth = Predefined	n8n credential used to sign the HTTP request.
Generic Auth Type	Yes	HTTP Auth = Generic	Generic auth credential used to sign the HTTP request.

Options

Option	Shown when	Description
Leg ID	Always	Explicit target leg.
HTTP Method	Output Type = HTTP	POST or PUT.
HTTP Headers	Output Type = HTTP	Extra HTTP headers.
Silence Threshold	Interrupt On contains Silence	Silence detection threshold.
Silence Duration (ms)	Interrupt On contains Silence	Silence duration required to stop recording.
Stop Other Media	Always	Stop other active media on the same leg first.
Execution Mode	Always	Blocking or Background.
WAV Sample Rate	File Format = WAV	WAV output sample rate.
WAV Bit Depth	File Format = WAV	WAV output bit depth.
Compressed Sample Rate	File Format = MP3, Opus, or OGG	Output sample rate for compressed formats.
Compressed Bitrate	File Format = MP3, Opus, or OGG	Output bitrate for compressed formats.

Output

Branch	When used	Typical fields
Result	Execution Mode = Background	mediaId, legId
Interrupted	Execution Mode = Blocking	mediaId, legId, interruptReason, optional digit
Completed	Execution Mode = Blocking	mediaId, legId, optional durationMs, optional bytesProduced, optional filePath

Operation: Stop Media

Parameters

Parameter	Required	Description
Target	Yes	Media ID or Leg ID.
Options -> Media ID	Yes when Target = Media ID	Explicit media operation to stop.
Options -> Leg ID	Yes when Target = Leg ID	Stop active media on this leg.

Output

Branch	Typical fields
Result	mediaId, optional legId

Operation: Wait Media

Parameters

Parameter	Required	Description
Timeout (Seconds)	No	Maximum wait time before the action takes the Timeout branch.
Media IDs	No	Explicit wait target list. If empty, resolves from item.json.mediaId, then item.json.sipPbx.mediaId.

Output

Branch	Typical fields
Interrupted	mediaId, legId, interruptReason, optional digit
Timeout	mediaId, optional legId, eventType = "timeout"
Completed	mediaId, legId, optional durationMs, optional bytesProduced, optional filePath

Wait Media and queued DTMF

• Media waits and blocking media actions use the same shared built-in interruptReason catalog as the other wait actions, but only the media subset relevant to that operation.
• Wait Media is media-scoped, not leg-scoped.
• If all watched media operations on a leg are non-interrupting for DTMF, Wait Media consumes queued and live leg DTMF while it waits.
• This mirrors the behavior of non-interrupting blocking media, where stray digits should not leak through into a later call.wait.
• If one of the watched media operations is DTMF-interruptible, Wait Media does not drain DTMF for that leg.
• Explicit Stop Media finalizes the stopped media with interruptReason = "media_stopped".
• If the underlying leg is destroyed while the media operation is still active, both Wait Media and blocking media actions resolve through Interrupted with interruptReason = "call_ended".
• If a leg is joined into a bridge by call.bridge, active media on that leg resolves through Interrupted with interruptReason = "call_bridge_joined".

Operation: Send DTMF

Parameters

Parameter	Required	Description
Digits	Yes	DTMF string to send.
Options -> Leg ID	No	Explicit target leg. If omitted, resolves from current item leg metadata.
Options -> Method	No	Auto, RFC2833, SIP INFO, or Inband.
Options -> Duration (ms)	No	Per-digit duration.
Options -> Gap (ms)	No	Gap between digits.

Output

Branch	Fields
Result	legId, digits

DTMF Notes

Topic	Behavior
Inbound methods	The runtime accepts inbound DTMF from RFC2833, SIP INFO, and optionally Inband audio-tone detection when allowed by the active SIP route.
Deduplication	Repeated RFC2833 retransmits are deduplicated. Short-window transport dedup also suppresses duplicate DTMF arriving from multiple methods such as RFC2833 plus SIP INFO.
Blocking media with Interrupt On	Blocking media actions take the Interrupted branch when the selected signal arrives.
Blocking media without Interrupt On = DTMF	Queued and live DTMF is consumed while the media waits, so stale digits do not leak into later leg waits.
Explicit Stop Media	Wait Media and blocking media on the stopped operation resolve through Interrupted with interruptReason = "media_stopped".
Leg destruction during active media	Active playback, tone, recording, and Wait Media complete through Interrupted with interruptReason = "call_ended" even if no user interrupt signal was selected.
Bridge activation during active media	Active playback, tone, recording, and Wait Media on that leg complete through Interrupted with interruptReason = "call_bridge_joined".