diff --git a/RGB.NET.Core/Groups/AbstractLedGroup.cs b/RGB.NET.Core/Groups/AbstractLedGroup.cs
index 7007152..eab6803 100644
--- a/RGB.NET.Core/Groups/AbstractLedGroup.cs
+++ b/RGB.NET.Core/Groups/AbstractLedGroup.cs
@@ -36,7 +36,7 @@ namespace RGB.NET.Core
         #region Methods
 
         /// <inheritdoc />
-        public abstract IEnumerable<Led> GetLeds();
+        public abstract IList<Led> GetLeds();
 
         /// <inheritdoc />
         public virtual void OnAttach()
diff --git a/RGB.NET.Core/Groups/ILedGroup.cs b/RGB.NET.Core/Groups/ILedGroup.cs
index 638f146..5db5e63 100644
--- a/RGB.NET.Core/Groups/ILedGroup.cs
+++ b/RGB.NET.Core/Groups/ILedGroup.cs
@@ -25,7 +25,7 @@ namespace RGB.NET.Core
         /// Gets a list containing all <see cref="Led"/> of this <see cref="ILedGroup"/>.
         /// </summary>
         /// <returns>The list containing all <see cref="Led"/> of this <see cref="ILedGroup"/>.</returns>
-        IEnumerable<Led> GetLeds();
+        IList<Led> GetLeds();
 
         /// <summary>
         /// Called when the <see cref="ILedGroup"/> is attached to the <see cref="RGBSurface"/>.
diff --git a/RGB.NET.Core/RGBSurface.cs b/RGB.NET.Core/RGBSurface.cs
index 9528f78..74bc882 100644
--- a/RGB.NET.Core/RGBSurface.cs
+++ b/RGB.NET.Core/RGBSurface.cs
@@ -38,7 +38,14 @@ namespace RGB.NET.Core
         /// <summary>
         /// Gets a readonly list containing all loaded <see cref="IRGBDevice"/>.
         /// </summary>
-        public IEnumerable<IRGBDevice> Devices => new ReadOnlyCollection<IRGBDevice>(_devices);
+        public IEnumerable<IRGBDevice> Devices
+        {
+            get
+            {
+                lock (_devices)
+                    return new ReadOnlyCollection<IRGBDevice>(_devices);
+            }
+        }
 
         /// <summary>
         /// Gets a readonly list containing all registered <see cref="IUpdateTrigger"/>.
@@ -53,7 +60,14 @@ namespace RGB.NET.Core
         /// <summary>
         /// Gets a list of all <see cref="Led"/> on this <see cref="RGBSurface"/>.
         /// </summary>
-        public IEnumerable<Led> Leds => _devices.SelectMany(x => x);
+        public IEnumerable<Led> Leds
+        {
+            get
+            {
+                lock (_devices)
+                    return _devices.SelectMany(x => x);
+            }
+        }
 
         #endregion
 
@@ -92,32 +106,33 @@ namespace RGB.NET.Core
                 bool updateDevices = customData["updateDevices"] as bool? ?? true;
 
                 lock (_updateTriggers)
-                {
-                    OnUpdating(updateTrigger, customData);
+                    lock (_devices)
+                    {
+                        OnUpdating(updateTrigger, customData);
 
-                    if (syncBack)
-                        foreach (IRGBDevice device in Devices)
-                            if (device.UpdateMode.HasFlag(DeviceUpdateMode.SyncBack) && device.DeviceInfo.SupportsSyncBack)
-                                try { device.SyncBack(); }
-                                catch (Exception ex) { OnException(ex); }
+                        if (syncBack)
+                            foreach (IRGBDevice device in _devices)
+                                if (device.UpdateMode.HasFlag(DeviceUpdateMode.SyncBack) && device.DeviceInfo.SupportsSyncBack)
+                                    try { device.SyncBack(); }
+                                    catch (Exception ex) { OnException(ex); }
 
-                    if (render)
-                        lock (_ledGroups)
-                        {
-                            // Render brushes
-                            foreach (ILedGroup ledGroup in _ledGroups.OrderBy(x => x.ZIndex))
-                                try { Render(ledGroup); }
-                                catch (Exception ex) { OnException(ex); }
-                        }
+                        if (render)
+                            lock (_ledGroups)
+                            {
+                                // Render brushes
+                                foreach (ILedGroup ledGroup in _ledGroups.OrderBy(x => x.ZIndex))
+                                    try { Render(ledGroup); }
+                                    catch (Exception ex) { OnException(ex); }
+                            }
 
-                    if (updateDevices)
-                        foreach (IRGBDevice device in Devices)
-                            if (!device.UpdateMode.HasFlag(DeviceUpdateMode.NoUpdate))
-                                try { device.Update(flushLeds); }
-                                catch (Exception ex) { OnException(ex); }
+                        if (updateDevices)
+                            foreach (IRGBDevice device in _devices)
+                                if (!device.UpdateMode.HasFlag(DeviceUpdateMode.NoUpdate))
+                                    try { device.Update(flushLeds); }
+                                    catch (Exception ex) { OnException(ex); }
 
-                    OnUpdated();
-                }
+                        OnUpdated();
+                    }
             }
             catch (Exception ex)
             {
@@ -128,20 +143,19 @@ namespace RGB.NET.Core
         /// <inheritdoc />
         public void Dispose()
         {
-            //if (_updateTokenSource?.IsCancellationRequested == false)
-            //    _updateTokenSource.Cancel();
+            lock (_devices)
+                foreach (IRGBDevice device in _devices)
+                    try { device.Dispose(); }
+                    catch { /* We do what we can */}
 
-            foreach (IRGBDevice device in _devices)
-                try { device.Dispose(); }
-                catch { /* We do what we can */ }
-
-            foreach (IRGBDeviceProvider deviceProvider in _deviceProvider)
-                try { deviceProvider.Dispose(); }
-                catch { /* We do what we can */ }
+            lock (_deviceProvider)
+                foreach (IRGBDeviceProvider deviceProvider in _deviceProvider)
+                    try { deviceProvider.Dispose(); }
+                    catch { /* We do what we can */}
 
             foreach (IUpdateTrigger updateTrigger in _updateTriggers)
                 try { updateTrigger.Dispose(); }
-                catch { /* We do what we can */ }
+                catch { /* We do what we can */}
 
             _ledGroups.Clear();
             _devices = null;
@@ -224,8 +238,11 @@ namespace RGB.NET.Core
 
         private void UpdateSurfaceRectangle()
         {
-            Rectangle devicesRectangle = new Rectangle(_devices.Select(d => d.DeviceRectangle));
-            SurfaceRectangle = SurfaceRectangle.SetSize(new Size(devicesRectangle.Location.X + devicesRectangle.Size.Width, devicesRectangle.Location.Y + devicesRectangle.Size.Height));
+            lock (_devices)
+            {
+                Rectangle devicesRectangle = new Rectangle(_devices.Select(d => d.DeviceRectangle));
+                SurfaceRectangle = SurfaceRectangle.SetSize(new Size(devicesRectangle.Location.X + devicesRectangle.Size.Width, devicesRectangle.Location.Y + devicesRectangle.Size.Height));
+            }
         }
 
         /// <summary>
@@ -235,7 +252,10 @@ namespace RGB.NET.Core
         /// <returns>A list of devices with the specified type.</returns>
         public IList<T> GetDevices<T>()
             where T : class
-            => new ReadOnlyCollection<T>(_devices.Select(x => x as T).Where(x => x != null).ToList());
+        {
+            lock (_devices)
+                return new ReadOnlyCollection<T>(_devices.Select(x => x as T).Where(x => x != null).ToList());
+        }
 
         /// <summary>
         /// Gets all devices of the specified <see cref="RGBDeviceType"/>.
@@ -243,7 +263,10 @@ namespace RGB.NET.Core
         /// <param name="deviceType">The <see cref="RGBDeviceType"/> of the devices to get.</param>
         /// <returns>a list of devices matching the specified <see cref="RGBDeviceType"/>.</returns>
         public IList<IRGBDevice> GetDevices(RGBDeviceType deviceType)
-            => new ReadOnlyCollection<IRGBDevice>(_devices.Where(d => deviceType.HasFlag(d.DeviceInfo.DeviceType)).ToList());
+        {
+            lock (_devices)
+                return new ReadOnlyCollection<IRGBDevice>(_devices.Where(d => deviceType.HasFlag(d.DeviceInfo.DeviceType)).ToList());
+        }
 
         /// <summary>
         /// Registers the provided <see cref="IUpdateTrigger"/>.
diff --git a/RGB.NET.Core/RGBSurfaceDeviceLoader.cs b/RGB.NET.Core/RGBSurfaceDeviceLoader.cs
index f233282..df760c3 100644
--- a/RGB.NET.Core/RGBSurfaceDeviceLoader.cs
+++ b/RGB.NET.Core/RGBSurfaceDeviceLoader.cs
@@ -29,28 +29,31 @@ namespace RGB.NET.Core
         /// <param name="throwExceptions">Specifies whether exception during the initialization sequence should be thrown or not.</param>
         public void LoadDevices(IRGBDeviceProvider deviceProvider, RGBDeviceType loadFilter = RGBDeviceType.All, bool exclusiveAccessIfPossible = false, bool throwExceptions = false)
         {
-            if (_deviceProvider.Contains(deviceProvider) || _deviceProvider.Any(x => x.GetType() == deviceProvider.GetType())) return;
-
-            List<IRGBDevice> addedDevices = new List<IRGBDevice>();
-            if (deviceProvider.IsInitialized || deviceProvider.Initialize(loadFilter, exclusiveAccessIfPossible, throwExceptions))
+            lock (_deviceProvider)
             {
-                _deviceProvider.Add(deviceProvider);
+                if (_deviceProvider.Contains(deviceProvider) || _deviceProvider.Any(x => x.GetType() == deviceProvider.GetType())) return;
 
-                foreach (IRGBDevice device in deviceProvider.Devices)
+                List<IRGBDevice> addedDevices = new List<IRGBDevice>();
+                if (deviceProvider.IsInitialized || deviceProvider.Initialize(loadFilter, exclusiveAccessIfPossible, throwExceptions))
                 {
-                    if (_devices.Contains(device)) continue;
+                    _deviceProvider.Add(deviceProvider);
+                    lock (_devices)
+                        foreach (IRGBDevice device in deviceProvider.Devices)
+                        {
+                            if (_devices.Contains(device)) continue;
 
-                    addedDevices.Add(device);
+                            addedDevices.Add(device);
 
-                    device.PropertyChanged += DeviceOnPropertyChanged;
-                    _devices.Add(device);
+                            device.PropertyChanged += DeviceOnPropertyChanged;
+                            _devices.Add(device);
+                        }
                 }
-            }
 
-            if (addedDevices.Any())
-            {
-                UpdateSurfaceRectangle();
-                SurfaceLayoutChanged?.Invoke(new SurfaceLayoutChangedEventArgs(addedDevices, true, false));
+                if (addedDevices.Any())
+                {
+                    UpdateSurfaceRectangle();
+                    SurfaceLayoutChanged?.Invoke(new SurfaceLayoutChangedEventArgs(addedDevices, true, false));
+                }
             }
         }
 
diff --git a/RGB.NET.Groups/Groups/ListLedGroup.cs b/RGB.NET.Groups/Groups/ListLedGroup.cs
index a5fed36..eb833d8 100644
--- a/RGB.NET.Groups/Groups/ListLedGroup.cs
+++ b/RGB.NET.Groups/Groups/ListLedGroup.cs
@@ -92,9 +92,10 @@ namespace RGB.NET.Groups
         {
             if (leds == null) return;
 
-            foreach (Led led in leds)
-                if ((led != null) && !ContainsLed(led))
-                    GroupLeds.Add(led);
+            lock (GroupLeds)
+                foreach (Led led in leds)
+                    if ((led != null) && !ContainsLed(led))
+                        GroupLeds.Add(led);
         }
 
         /// <summary>
@@ -111,9 +112,10 @@ namespace RGB.NET.Groups
         {
             if (leds == null) return;
 
-            foreach (Led led in leds)
-                if (led != null)
-                    GroupLeds.Remove(led);
+            lock (GroupLeds)
+                foreach (Led led in leds)
+                    if (led != null)
+                        GroupLeds.Remove(led);
         }
 
         /// <summary>
@@ -121,7 +123,11 @@ namespace RGB.NET.Groups
         /// </summary>
         /// <param name="led">The LED which should be checked.</param>
         /// <returns><c>true</c> if the LED is contained by this ledgroup; otherwise, <c>false</c>.</returns>
-        public bool ContainsLed(Led led) => (led != null) && GroupLeds.Contains(led);
+        public bool ContainsLed(Led led)
+        {
+            lock (GroupLeds)
+                return (led != null) && GroupLeds.Contains(led);
+        }
 
         /// <summary>
         /// Merges the <see cref="Led"/> from the given ledgroup in this ledgroup. 
@@ -129,9 +135,10 @@ namespace RGB.NET.Groups
         /// <param name="groupToMerge">The ledgroup to merge.</param>
         public void MergeLeds(ILedGroup groupToMerge)
         {
-            foreach (Led led in groupToMerge.GetLeds())
-                if (!GroupLeds.Contains(led))
-                    GroupLeds.Add(led);
+            lock (GroupLeds)
+                foreach (Led led in groupToMerge.GetLeds())
+                    if (!GroupLeds.Contains(led))
+                        GroupLeds.Add(led);
         }
 
         /// <inheritdoc />
@@ -139,7 +146,11 @@ namespace RGB.NET.Groups
         /// Gets a list containing the <see cref="T:RGB.NET.Core.Led" /> from this group.
         /// </summary>
         /// <returns>The list containing the <see cref="T:RGB.NET.Core.Led" />.</returns>
-        public override IEnumerable<Led> GetLeds() => GroupLeds;
+        public override IList<Led> GetLeds()
+        {
+            lock (GroupLeds)
+                return new List<Led>(GroupLeds);
+        }
 
         #endregion
     }
diff --git a/RGB.NET.Groups/Groups/RectangleLedGroup.cs b/RGB.NET.Groups/Groups/RectangleLedGroup.cs
index 1b23c26..90bb88c 100644
--- a/RGB.NET.Groups/Groups/RectangleLedGroup.cs
+++ b/RGB.NET.Groups/Groups/RectangleLedGroup.cs
@@ -105,7 +105,7 @@ namespace RGB.NET.Groups
         /// Gets a list containing all <see cref="T:RGB.NET.Core.Led" /> of this <see cref="T:RGB.NET.Groups.RectangleLedGroup" />.
         /// </summary>
         /// <returns>The list containing all <see cref="T:RGB.NET.Core.Led" /> of this <see cref="T:RGB.NET.Groups.RectangleLedGroup" />.</returns>
-        public override IEnumerable<Led> GetLeds() => _ledCache ??= RGBSurface.Instance.Leds.Where(led => led.AbsoluteLedRectangle.CalculateIntersectPercentage(Rectangle) >= MinOverlayPercentage).ToList();
+        public override IList<Led> GetLeds() => _ledCache ??= RGBSurface.Instance.Leds.Where(led => led.AbsoluteLedRectangle.CalculateIntersectPercentage(Rectangle) >= MinOverlayPercentage).ToList();
 
         private void InvalidateCache() => _ledCache = null;