         handleUpdateParam(slider2)
     }
 
+    private func updateInfo() {
+        chooseAudioButton.isEnabled = node == player
+        inputSourceInfo.stringValue = node == player ? "🔊 \(audioTitle)" : "🔊 ⏦ \(oscillator.frequency) hz"
+    }
     private func initOscillator() {
         guard node != oscillator else { return }
         booster.disconnectInput()

    var player: AKPlayer?
    var node: AKNode? {
        didSet {
            chooseAudioButton.isEnabled = node == player
            inputSourceInfo.stringValue = node == player ? "🔊 \(audioTitle)" : "🔊 ⏦ \(oscillator.frequency) hz"
        }
    }


            chooseAudio(chooseAudioButton)
            return
        }
        updateInfo()
        guard node != player else { return }
        guard let player = player else { return }

