[Bug]: Unable to contact server. StatusCode: 1006, <endpoint> Reason:

[keithyipkw]

What happened?

TTS used to work a few weeks ago, but now fails in the SDK while STT is still fine. The problem can be reproduced by running the sample at https://github.com/Azure-Samples/cognitive-services-speech-sdk/tree/master/samples/js/node.

settings.js:

export const subscriptionKey =   "YourSubscriptionKey";
export const serviceEndpoint =   "https://southeastasia.api.cognitive.microsoft.com"; // e.g., "https://westus.api.cognitive.microsoft.com"
export const serviceRegion =     "southeastasia"; // e.g., "westus"
export const language =          "en-US";

// Replace with the full path to a wav file you want to recognize or overwrite.
export const filename =          "YourAudioFile.wav"; // 16000 Hz, Mono

However, the REST version works.

curl --location --request POST "https://southeastasia.tts.speech.microsoft.com/cognitiveservices/v1" \
--header "Ocp-Apim-Subscription-Key: %SPEECH_KEY%"" \
--header "Content-Type: application/ssml+xml" \
--header "X-Microsoft-OutputFormat: audio-16khz-128kbitrate-mono-mp3" \
--header "User-Agent: curl" \
--data-raw "<speak version='1.0' xml:lang='en-US'><voice xml:lang='en-US' xml:gender='Female' name='en-us-Ava:DragonHDLatestNeural'>hello</voice></speak>" --output output.mp3

The error seems to be first caught by this.privWebsocketClient.onerror in WebsocketMessageAdapter.js. If I do WebsocketMessageAdapter.forceNpmWebSocket = true; before the connection, TTS seems to work.

WebsocketMessageAdapter.js:

    open() {
        if (this.privConnectionState === Exports_js_1.ConnectionState.Disconnected) {
            return Promise.reject(`Cannot open a connection that is in ${this.privConnectionState} state`);
        }
        if (this.privConnectionEstablishDeferral) {
            return this.privConnectionEstablishDeferral.promise;
        }
        this.privConnectionEstablishDeferral = new Exports_js_1.Deferred();
        this.privCertificateValidatedDeferral = new Exports_js_1.Deferred();
        this.privConnectionState = Exports_js_1.ConnectionState.Connecting;
        try {
            if (typeof WebSocket !== "undefined" && !WebsocketMessageAdapter.forceNpmWebSocket) {
                // Browser handles cert checks.
                this.privCertificateValidatedDeferral.resolve();
                this.privWebsocketClient = new WebSocket(this.privUri);
            }
            else {
                // Workaround for https://github.com/microsoft/cognitive-services-speech-sdk-js/issues/465
                // Which is root caused by https://github.com/TooTallNate/node-agent-base/issues/61
                const uri = new URL(this.privUri);
                let protocol = uri.protocol;
                if (protocol?.toLocaleLowerCase() === "wss:") {
                    protocol = "https:";
                }
                else if (protocol?.toLocaleLowerCase() === "ws:") {
                    protocol = "http:";
                }
                const options = { headers: this.privHeaders, perMessageDeflate: this.privEnableCompression, followRedirects: protocol.toLocaleLowerCase() === "https:" };
                // The ocsp library will handle validation for us and fail the connection if needed.
                this.privCertificateValidatedDeferral.resolve();
                options.agent = this.getAgent();
                // eslint-disable-next-line @typescript-eslint/no-unsafe-member-access
                options.agent.protocol = protocol;
                this.privWebsocketClient = new ws_1.default(this.privUri, options);
                this.privWebsocketClient.on("redirect", (redirectUrl) => {
                    const event = new Exports_js_1.ConnectionRedirectEvent(this.privConnectionId, redirectUrl, this.privUri, `Getting redirect URL from endpoint ${this.privUri} with redirect URL '${redirectUrl}'`);
                    Exports_js_1.Events.instance.onEvent(event);
                });
            }
            this.privWebsocketClient.binaryType = "arraybuffer";
            this.privReceivingMessageQueue = new Exports_js_1.Queue();
            this.privDisconnectDeferral = new Exports_js_1.Deferred();
            this.privSendMessageQueue = new Exports_js_1.Queue();
            this.processSendQueue().catch((reason) => {
                Exports_js_1.Events.instance.onEvent(new Exports_js_1.BackgroundEvent(reason));
            });
        }
        catch (error) {
            this.privConnectionEstablishDeferral.resolve(new Exports_js_1.ConnectionOpenResponse(500, error));
            return this.privConnectionEstablishDeferral.promise;
        }
        this.onEvent(new Exports_js_1.ConnectionStartEvent(this.privConnectionId, this.privUri));
        this.privWebsocketClient.onopen = () => {
            this.privCertificateValidatedDeferral.promise.then(() => {
                this.privConnectionState = Exports_js_1.ConnectionState.Connected;
                this.onEvent(new Exports_js_1.ConnectionEstablishedEvent(this.privConnectionId));
                this.privConnectionEstablishDeferral.resolve(new Exports_js_1.ConnectionOpenResponse(200, ""));
            }, (error) => {
                this.privConnectionEstablishDeferral.reject(error);
            });
        };
        this.privWebsocketClient.onerror = (e) => {
            this.onEvent(new Exports_js_1.ConnectionErrorEvent(this.privConnectionId, e.message, e.type));
            this.privLastErrorReceived = e.message;
        };

Version:
1.48.0, 1.47.0

Platform:
Node v25.1.0
docker node:lts-alpine3.23, Windows 10

Version

1.48.0 (Latest, Default)

What browser/platform are you seeing the problem on?

Node

Relevant log output

Now synthesizing to: YourAudioFile.wav
Type some text that you want to speak...
> a
(cancel) Reason: Error: Unable to contact server. StatusCode: 1006,
                    https://southeastasia.api.cognitive.microsoft.com/tts/cognitiveservices/websocket/v1 Reason: