     var audioEnabled: Bool { get set }
 
     /**
-     音声のボリューム。 0 から 10 (含む) までの値をセットします。
+     受信した音声のボリューム。 0 から 10 (含む) までの値をセットします。
      このプロパティはロールがサブスクライバーの場合のみ有効です。
      */
-    var audioVolume: Double? { get set }
+    var remoteAudioVolume: Double? { get set }
     
     // MARK: 映像フレームの送信
 

        self.nativeStream = nativeStream
        streamId = nativeStream.streamId
        creationTime = Date()
        cachedNativeVideoTrack = nativeStream.videoTracks.first
        cachedNativeAudioTrack = nativeStream.audioTracks.first
    }
    
    private static let dummyCapturer: RTCVideoCapturer = RTCVideoCapturer()

    var nativeStream: RTCMediaStream
    
    var nativeVideoTrack: RTCVideoTrack? {
        return nativeStream.videoTracks.first
    }
    
    var nativeVideoSource: RTCVideoSource? {
        return nativeVideoTrack?.source
    }
    
    var nativeAudioTrack: RTCAudioTrack? {
        return nativeStream.audioTracks.first
    }
    
    var videoEnabled: Bool {
        get {
            return nativeVideoTrack != nil ? nativeVideoTrack!.isEnabled : false
        }
        set {
            guard videoEnabled != newValue else {
                return
            }
            if let track = nativeVideoTrack {
                track.isEnabled = newValue
                handlers.onSwitchVideoHandler?(newValue)
            }
        }
    }
    
    var audioEnabled: Bool {
        get {
            return nativeAudioTrack != nil ? nativeAudioTrack!.isEnabled : false
        }
        set {
            guard audioEnabled != newValue else {
                return
            }
            if let track = nativeAudioTrack {
                track.isEnabled = newValue
                handlers.onSwitchAudioHandler?(newValue)
            }
        }
    }
    
    var remoteAudioVolume: Double? {
        get {
            return nativeAudioTrack?.source.volume
        }
        set {
            guard let newValue = newValue else {
                return
            }
            if let track = nativeAudioTrack {
                var volume = newValue
                if volume < MediaStreamAudioVolume.min {
                    volume = MediaStreamAudioVolume.min
                } else if volume > MediaStreamAudioVolume.max {
                    volume = MediaStreamAudioVolume.max
                }
                track.source.volume = volume
                Logger.debug(type: .mediaStream,
                             message: "set audio volume \(volume)")
            }
        }
    }
