Mute or Unmute a Remote User in Agora RTC with Signaling

Overview

This article provides step-by-step instructions for implementing the mute and unmute functionality for remote users in your video calling application using the Agora RTC and Signaling SDKs. This feature allows the host to manage the audio streams of participants effectively during a call.

Prerequisites

Before you begin, ensure you have the following:

• Agora RTC SDK integrated into your application.
• Agora Signaling SDK integrated into your application.
• All users must be subscribed to the Signaling channel.

Issue Description

Symptoms

You want to allow the host to mute or unmute a remote user's audio stream, making it so that all users in the channel will not hear the muted user's audio.

Root Cause

The mute/unmute functionality requires the use of the Agora Signaling SDK to send real-time notifications to the remote users.

Resolution Steps

Step 1: Set Up Signaling

Follow the Signaling Quickstart guide to set up the Signaling SDK in your application. You can find the instructions here: Agora Signaling Quickstart.

Step 2: Subscribe to the Signaling Channel

Ensure that all users in the video call are subscribed to the same Signaling channel to receive mute/unmute commands.

Step 3: Implement Mute/Unmute Logic

Add the following code to your host client to mute a remote user:

function muteRemoteUser(userId) {
    // Send a message to the remote user to mute
    signalingClient.sendMessage({
        text: JSON.stringify({ action: "mute", userId: userId })
    });
}

On the remote user side, listen for incoming messages and handle the mute/unmute action:

signalingClient.on('messageReceived', (message) = {
    const data = JSON.parse(message.text);
    if (data.action === "mute" && data.userId === yourUserId) {
        // Mute the audio stream
        localStream.muteAudio();
    }
});

Step 4: Unmute Remote User

To unmute a user, send a similar message with the action set to "unmute" and handle it the same way on the remote user side.

function unmuteRemoteUser(userId) {
    signalingClient.sendMessage({
        text: JSON.stringify({ action: "unmute", userId: userId })
    });
}

Additional Information

For more detailed information about the Agora RTC and Signaling SDKs, refer to the official documentation:

• Agora RTC Documentation
• Agora Signaling Documentation

Validation and Confirmation

Tested On

Tested on Agora RTC SDK v4.0.0 and Signaling SDK v1.0.0.

Expected Outcome

Once implemented, the host should be able to mute or unmute remote users successfully, preventing or allowing audio from those users during the call.

FAQ

Can I mute multiple users at once?

Yes, you can send separate mute messages for each user you want to mute.

What if a user re-joins the call?

You will need to resend the mute command for any user that was previously muted when they re-join the call.