---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/16000#article
headline: "16000: Whisper Not Available on Twilio Conference"
url: https://www.twilio.com/docs/api/errors/16000
inLanguage: en
dateModified: 2026-03-20T20:33:25.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 16000: Whisper Not Available on Twilio Conference

Log Level: ERROR

## Description

This error occurs when you try to use `whisper` or coaching on a standard Voice Conference. Whispering is available only on Agent Conference, and Twilio Conference supports participant coaching in that mode.

### Possible causes

* You attempted to set up `whisper` on a conference that was created without Agent Conference enabled.
* Your account is configured for standard Conference instead of Agent Conference, so the conference leg does not support agent whispering.

### Possible solutions

* Enable Agent Conference in the Twilio Console conference settings, then create the conference again with Agent Conference enabled.
* Use the Agent Conference coaching flow when you need a supervisor to speak privately to one participant without others hearing the audio.

#### Additional resources

* [Voice Conference](/docs/voice/conference)
* [TwiML Voice: `<Conference>`](/docs/voice/twiml/conference)