Echo cancellation does not work as expected

[leson1106]

Describe the bug
Echo Cancellation did not work even if I enable all these properties for Room and LocalParticipant. This led to duplicate message as shown below, because Audio Engine often take output voice as the input as well.

Related thread on Slack.

try await liveKitRoom.connect(
    url: url,
    token: token,
    connectOptions: ConnectOptions(
        reconnectAttempts     : 1000,
        reconnectAttemptDelay : 3
    ),
    roomOptions: RoomOptions(
        defaultAudioCaptureOptions: .init(
            echoCancellation: true,
            noiseSuppression: true,
            autoGainControl: true,
            typingNoiseDetection: true,
            highpassFilter: true
        )
    )
)
try await localParticipant.setMicrophone(
    enabled: true,
    captureOptions: .init(
        echoCancellation: true,
        noiseSuppression: true,
        autoGainControl: true,
        typingNoiseDetection: true,
        highpassFilter: true
    )
)

SDK Version
2.0.14 and also upgraded to the latest version but no luck

iOS/macOS Version
iOS 18.1 and iOS 17.5

Xcode Version
Xcode 15.4.0 and Xcode 16.0.0

Steps to Reproduce
It's quite easy to reproduce just by creating a room, enable localParticipant microphone, and then start talking to each other.

Expected behavior
The transcriptions that received from delegate need to be filtered by echo cancellation somehow.

func room(_:participant:trackPublication:didReceiveTranscriptionSegments:)

Screenshots

[hiroshihorie]

Hi, working on an AVAudioEngine version which hope fully does better.