diff --git a/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
index 2f23ffe0..203d06a5 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
@@ -43,10 +43,10 @@ namespace HandyControl.Controls
         {
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(SelectedValueProperty);
-                ClearValue(SelectedItemProperty);
-                ClearValue(SelectedIndexProperty);
-                ClearValue(TextProperty);
+                SetCurrentValue(SelectedValueProperty, null);
+                SetCurrentValue(SelectedItemProperty, null);
+                SetCurrentValue(SelectedIndexProperty, -1);
+                SetCurrentValue(TextProperty, "");
             }));
         }
 
@@ -85,7 +85,7 @@ namespace HandyControl.Controls
                             UpdateSourceTrigger = UpdateSourceTrigger.PropertyChanged,
                             Mode = BindingMode.OneWayToSource,
 #if !netle40
-                            Delay = 500,              
+                            Delay = 500,
 #endif
                             Source = this
                         });
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
index 993541ec..51642a31 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
@@ -20,8 +20,8 @@ namespace HandyControl.Controls
         {
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(SelectedDateProperty);
-                ClearValue(TextProperty);
+                SetCurrentValue(SelectedDateProperty, null);
+                SetCurrentValue(TextProperty, "");
             }));
         }
 
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
index c76112b6..55427b99 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
@@ -82,8 +82,8 @@ namespace HandyControl.Controls
             InitCalendarWithClock();
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(SelectedDateTimeProperty);
-                ClearValue(TextProperty);
+                SetCurrentValue(SelectedDateTimeProperty, null);
+                SetCurrentValue(TextProperty, "");
                 _textBox.Text = string.Empty;
             }));
         }
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs b/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
index df9f0c73..5f8f3f48 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
@@ -43,7 +43,7 @@ namespace HandyControl.Controls
             }));
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(ValueProperty);
+                SetCurrentValue(ValueProperty, 0d);
                 _textBox.Text = string.Empty;
             }));
 
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
index abfc12a3..8cc0edf5 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
@@ -15,7 +15,7 @@ namespace HandyControl.Controls
         {
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(TextProperty);
+                SetCurrentValue(TextProperty, "");
             }));
         }
 
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
index 021d7f7a..c696a244 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
@@ -80,8 +80,8 @@ namespace HandyControl.Controls
             Clock = new Clock();
             CommandBindings.Add(new CommandBinding(ControlCommands.Clear, (s, e) =>
             {
-                ClearValue(SelectedTimeProperty);
-                ClearValue(TextProperty);
+                SetCurrentValue(SelectedTimeProperty, null);
+                SetCurrentValue(TextProperty, "");
                 _textBox.Text = string.Empty;
             }));
         }
@@ -497,29 +497,29 @@ namespace HandyControl.Controls
             switch (e.Key)
             {
                 case Key.System:
-                {
-                    switch (e.SystemKey)
                     {
-                        case Key.Down:
+                        switch (e.SystemKey)
                         {
-                            if ((Keyboard.Modifiers & ModifierKeys.Alt) == ModifierKeys.Alt)
-                            {
-                                TogglePopUp();
-                                return true;
-                            }
+                            case Key.Down:
+                                {
+                                    if ((Keyboard.Modifiers & ModifierKeys.Alt) == ModifierKeys.Alt)
+                                    {
+                                        TogglePopUp();
+                                        return true;
+                                    }
 
-                            break;
+                                    break;
+                                }
                         }
+
+                        break;
                     }
 
-                    break;
-                }
-
                 case Key.Enter:
-                {
-                    SetSelectedTime();
-                    return true;
-                }
+                    {
+                        SetSelectedTime();
+                        return true;
+                    }
             }
 
             return false;