Zure Text-to-Speech API with the HTTP Request node in n8n

[Sergio_AT_Peixoto]

Hi everyone

I’m trying to use the Azure Text-to-Speech API with the HTTP Request node in n8n, but I keep getting a 400 - Bad Request error.

Here’s my setup:

• Method: POST
• URL: https://eastus.tts.speech.microsoft.com/cognitiveservices/v1
• Content-Type: application/ssml+xml
• Body: Raw SSML (confirmed valid)
• Output format: audio-48khz-192kbitrate-mono-mp3

Headers I used:

• Ocp-Apim-Subscription-Key: set with valid key
• X-Microsoft-OutputFormat:
• User-Agent: n8n-client
• Content-Type: application/ssml+xml

I tried both using “Generic Credential (Header Auth)” and also “None” with manual headers — still getting 400.

What’s the correct way to authenticate Azure Speech in n8n or configure credentials to allow multiple headers?

Thanks in advance

Here’s some screenshots of my node setup: