Hi @Lajos Sebestyen Szabo Greetings! Greetings! Welcome to Microsoft Q&A forum. Thank you for posting this question here.
I want to check with you and confirm if you are testing the Azure AI Speech recognition on Azure Kinect DK device and not Kinect for Windows V2 As per the documentation the speech services work on Azure Percept DK and Azure Kinect DK devices. Please refer the Device deployment kits for compatibility.
I have also looked into the Features supported for Kinect for Windows V2 and could not find the support for Speech recognition. Please refer the below image for details
Please ensure you are testing the SDK on the compatible device. Hope this helps. Please let us know if you have any additional questions on this.
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