We have a new authentication endpoint for speech API, which went live on 9/21/2016. The endpoint was deployed to multiple regions, so non-US clients can get better performance for authentication.
The previous endpoint has been depreciated and will no longer be available effective 3/21/2017. Please download the latest SDK or refer to latest sample code for REST to use the new endpoint.Azure users must create a new account of speech API or regenerate the existing keys to to use the new endpoint. The old keys (created before 9/21/2016) will not work with the new endpoint.