---
"@context": https://schema.org
"@type": TechArticle
"@id": https://www.twilio.com/docs/api/errors/17556#article
headline: "17556: Media format is not supported"
url: https://www.twilio.com/docs/api/errors/17556
inLanguage: en
dateModified: 2026-09-17T18:23:40.000Z
author:
  "@type": Organization
  name: Twilio Developer Education Team
publisher:
  "@type": Organization
  name: Twilio
---

# 17556: Media format is not supported

Log Type: APPLICATION

Log Level: ERROR

## Description

Twilio could not transcribe the recording because the media format is not supported. The transcription is marked as `failed`.

### Possible causes

* The media file is not in a supported format.

### Solutions

* Convert the recording to a supported format—WAV, MP3, or FLAC—and resubmit the transcription request.

### Additional resources

* [Transcribe an external recording](/docs/voice/api/batch-transcription-resource#transcribe-an-external-recording)