---
title: "Live streaming recognition issue"
slug: "ai-application-service-clovaspeech-troubleshoot-grpc"
updated: 2026-09-17T09:35:47Z
published: 2026-09-17T09:35:47Z
canonical: "api.ncloud-docs.com/ai-application-service-clovaspeech-troubleshoot-grpc"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://api.ncloud-docs.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Live streaming recognition issue

Available in Classic and VPC

You may experience the following situations while using the CLOVA Speech service. Check the questions and answers and act accordingly.

## Guide to managing gRPC connections

I would like to know if there is a recommended connection management method for gRPC connections.

#### Solution

1. When you finish using voice recognition, we recommend that you manage the channel by closing the gRPC connection.
  - You can use common development codes such as `channel.shutdown` and `channel.close` to close the channel. For a detailed example, see the content of [Real-time streaming recognition](/docs/en/ai-application-service-clovaspeech-example02).
  - You can maintain the channel connection by maintaining a single stream unit in which voice recognition requests are continuously made.
    - Example: In the case of a live broadcast, terminate the gRPC connection at the end of the live broadcast.
2. It is recommended to apply timeout logic according to the transmission/reception of voice recognition data.
  - If the connection is maintained without transmission/reception, problems may occur in acquiring the gRPC channel.

## Whether gRPC service has connection lifetime limit

I would like to know if there is a limit to the connection lifetime (the duration of the connection between the server and client) for the gRPC service.

#### Solution

Although the gRPC service has a connection lifetime limit set to 5 minutes, disconnections may occur due to network issues or other factors. Therefore, we recommend implementing a retry (reconnection) mechanism to ensure stable service operation.

## Whether gRPC service pausing is supported

I would like to know if the gRPC service supports pausing.

#### Solution

The gRPC service does not support pausing, but it can be implemented in the Recognize API by setting the `epFlag` entry in the `extraContents` field to `true`, sending a request, and then not making a Recognize request for a period of time. For more information about the `epFlag` entry, see [CLOVA Speech live streaming API](/docs/en/ai-application-service-clovaspeech-grpc).

- If you request Recognize without setting `epFlag` to `true` and do not re-request for a certain period of time, the server processes the buffered Recognize request based on `unvoiceTime` (10 seconds) set internally and displays the response results.

## Usage of `epFlag` and `seqId` in `extraContents` field

I would like to know the usage of `epFlag` and `seqId` in the `extraContents` field of the Recognize API.

#### Solution

You can use them for pausing purposes, or to check if you have received a complete response to a request you sent.

## Whether all responses have been received

I would like to know if I have received all the responses to the request I sent.

#### Solution

When calling the Recognize API, you can leverage the `epFlag` and `seqId` entries in the `extraContents` field. The result of a Recognize request with `epFlag` entry set to `true` and `seqId` entry set to any non-zero value can be verified by comparing `epFlag` and `seqId` in the Recognize response. For more information, see the JSON response body of [Recognize response](/docs/en/ai-application-service-clovaspeech-grpc#6-recognize-%EC%9D%91%EB%8B%B5).

## Whether `epFlag` value is required to be `true` before calling Close API

I would like to know if it is mandatory to set the `epFlag` entry to `true` in the Recognize API's `extraContents` before calling the Close API.

#### Solution

It is not mandatory to set the `epFlag` item to `true`. However, it is recommended to set the `epFlag` entry to `true` if you want to receive a fast response result for the last Recognize request. For more information about the `epFlag` entry, see [CLOVA Speech live streaming API](/docs/en/ai-application-service-clovaspeech-grpc).

## Recognize API sound source data format

I would like to know about the sound source data format for the Recognize API.

#### Solution

Currently, we only support PCM (headerless raw wave) format at 16 kHz, 1 channel, 16 bits per sample.