diff --git a/MTMR/VolumeViewController.swift b/MTMR/VolumeViewController.swift
index 73517f1..b73aeb7 100644
--- a/MTMR/VolumeViewController.swift
+++ b/MTMR/VolumeViewController.swift
@@ -16,6 +16,39 @@ class VolumeViewController: NSCustomTouchBarItem {
         }
 
         self.view = sliderItem
+        
+        var forPropertyAddress = AudioObjectPropertyAddress(
+            mSelector: kAudioHardwareServiceDeviceProperty_VirtualMasterVolume,
+            mScope: kAudioDevicePropertyScopeOutput,
+            mElement: kAudioObjectPropertyElementMaster)
+        
+        addListenerBlock(listenerBlock: audioObjectPropertyListenerBlock,
+                         onAudioObjectID: defaultDeviceID,
+                         forPropertyAddress: &forPropertyAddress)
+    }
+    
+    func addListenerBlock( listenerBlock: @escaping AudioObjectPropertyListenerBlock, onAudioObjectID: AudioObjectID, forPropertyAddress: UnsafePointer<AudioObjectPropertyAddress>) {
+
+        if (kAudioHardwareNoError != AudioObjectAddPropertyListenerBlock(onAudioObjectID, forPropertyAddress, nil, listenerBlock)) {
+            print("Error calling: AudioObjectAddPropertyListenerBlock") }
+    }
+    
+    func audioObjectPropertyListenerBlock (numberAddresses: UInt32, addresses: UnsafePointer<AudioObjectPropertyAddress>) {
+        var index: UInt32 = 0
+        while index < numberAddresses {
+            let address: AudioObjectPropertyAddress = addresses[Int(index)]
+            switch address.mSelector {
+            case kAudioHardwareServiceDeviceProperty_VirtualMasterVolume:
+                DispatchQueue.main.async {
+                    self.sliderItem.floatValue = self.getInputGain() * 100
+                }
+            default:
+                
+                print("We didn't expect this!")
+                
+            }
+            index += 1
+        }
     }
     
     required init?(coder: NSCoder) {
@@ -24,7 +57,7 @@ class VolumeViewController: NSCustomTouchBarItem {
     
     @objc func sliderValueChanged(_ sender: Any) {
         if let sliderItem = sender as? NSSlider {
-            setInputGain(Float32(sliderItem.intValue)/100.0)
+            _ = setInputGain(Float32(sliderItem.intValue)/100.0)
         }
     }
     
@@ -52,13 +85,30 @@ class VolumeViewController: NSCustomTouchBarItem {
     
     private func setInputGain(_ volume: Float32) -> OSStatus {
         var inputVolume: Float32 = volume
+        
+        if inputVolume == 0.0 {
+           _ = setMute( mute: 1)
+        } else {
+            _ = setMute( mute: 0)
+        }
+        
         let size: UInt32 = UInt32(MemoryLayout.size(ofValue: inputVolume))
         var address: AudioObjectPropertyAddress = AudioObjectPropertyAddress()
-        address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
         address.mScope = AudioObjectPropertyScope(kAudioDevicePropertyScopeOutput)
         address.mElement = AudioObjectPropertyElement(kAudioObjectPropertyElementMaster)
+        address.mSelector = AudioObjectPropertySelector(kAudioHardwareServiceDeviceProperty_VirtualMasterVolume)
         return AudioObjectSetPropertyData(defaultDeviceID, &address, 0, nil, size, &inputVolume)
     }
+    
+    private func setMute( mute: Int) -> OSStatus {
+        var muteVal: Int = mute
+        var address: AudioObjectPropertyAddress = AudioObjectPropertyAddress()
+        address.mSelector = AudioObjectPropertySelector(kAudioDevicePropertyMute)
+        let size: UInt32 = UInt32(MemoryLayout.size(ofValue: muteVal))
+        address.mScope = AudioObjectPropertyScope(kAudioDevicePropertyScopeOutput)
+        address.mElement = AudioObjectPropertyElement(kAudioObjectPropertyElementMaster)
+        return AudioObjectSetPropertyData(defaultDeviceID, &address, 0, nil, size, &muteVal)
+    }
 }
 
 class CustomSliderCell: NSSliderCell {