experimentalControls: { speed: 0.2, }, or experimentalControls: { speed: "slowest", }, Doesn't do anything at all, the voice is coming out at the speed of light! Also, we cannot use the VAPI controls (speed), as the cartesia API do not have the "speed" key https://cdn.discordapp.com/attachments/1377532876371001405/1377533459743903774/image.png?ex=68394f82&is=6837fe02&hm=e3266715cd701edbd9cf8317da5f26323d30bc375f70f86d40916211a5770efe&

Use experimental controls inside the voice object, but note that not all voices support it, and Cartesia may not fully implement speed adjustments yet.

Hey Kings, it's inside the voice object

If you provide a call id, we can review the logs to check if the setting appears in the assistant configuration.

Thanks Kyle, i'll do now

Looking into it

Thanks mate, also if you can let me know how do I know which voice has the control that would be great!

I see in the configuration that you are using 11labs, which supports voice speed adjustments. Are you configuring this through the dashboard?

It's overrided by the API

Hey! To help track down this issue, could you share: - The call ID - When exactly this happened (the timestamp) - What response you expected to get - What response you actually got instead This would really help us figure out what went wrong!

a426940e-15b4-4560-a8bd-4fe78c7ae821 2025-06-02T06:32:07.840Z Cartesia using the "SLOW" speed.

Hey, I checked with the team. This feature is still in an experimental state, so it's supposed to work sometimes with a few hiccups.

@Shubham Bajaj it's not working 100% of the time 🤣

Alberto, I completely understand your frustration and circumstances. Currently, I am gathering your feedback to forward it to the team. If the errors account for more than 20% of your total calls, kindly share the call_ids of those specific calls that encountered issues.

Shub, it's all of them; I don't think is Cartesia fault, i think is more VAPI not seeting the right configuraiaton; When i use Cartesia indipendetly the settings works.

This request is still pending and under investigation. Thank you for your patience

Hi Kyle, any update? We have customer complaining

Hey @Alberto , I apologize for not getting back to you earlier this weekend. I understand that something is broken and quite frustrating over the past month, as mentioned. It was in the experimental stage, but we didn't have it reported by others. I don't have the call_ids that I can refer to. I know you're dealing with these issues. If you can share the call_ids along with the timestamp and the expected voice responses against the actual voice responses. I can get in touch with the Cartesia team to get it resolved this week.

It's every single call done with Cartesia. Last 3: Settings were on the 'SLOW': e30cb0ba-0af8-4b6c-ada6-1aeba2c2e6eb 4af17758-2ba6-4934-ae23-ae35abe2fade 79ce2099-2a2d-43e7-b690-fadb1f5c5534

Looking Into these calls.

Thanks 🙂

Hey, the issue has been identified and it will be resolved in the upcoming releases. I cannot give you an eta as it depends on the team, on-going tasks, and availability.

We are trying to set experimentalControls for Cartesia and getting a 500 error: voice: model: sonic-3 voiceId: 728ae069-c690-444e-881f-55b66db143ce provider: cartesia experimentalControls: emotion: - name: positivity level: high - name: curiosity level: high 📋 Step 5: Updating existing assistant via Vapi API... 🔄 Updating assistant d7705805-d1ce-4d8d-8c92-3d0cefda0554... ❌ Vapi API Update Error Details: • Response Body: { "statusCode": 500, "message": "Internal server error. Contact support@vapi.ai for help." } • Error Message: Status code: 500 Body: { "statusCode": 500, "message": "Internal server error. Contact support@vapi.ai for help." } ❌ Failed to create assistant: Failed to update assistant: Status code: 500 Body: { "statusCode": 500, "message": "Internal server error. Contact support@vapi.ai for help." } ❌ Error: Process exited with code 1 Error: Process completed with exit code 1.