В чем может быть причина эксэпшина FormatException (Input string was not in a correct format.) после вызова PropertyChangedEventHandler?

Репродюситься не всегда, а при определеном порядке действий на юае для то й же самой проперти.

Картина в атаче.

mscorlib.dll!System.Number.StringToNumber(string str, System.Globalization.NumberStyles options, ref System.Number.NumberBuffer number, System.Globalization.NumberFormatInfo info, bool parseDecimal) + 0xf7 bytes
mscorlib.dll!System.Number.ParseInt32(string s, System.Globalization.NumberStyles style, System.Globalization.NumberFormatInfo info) + 0x92 bytes
mscorlib.dll!string.System.IConvertible.ToInt32(System.IFormatProvider provider) + 0x2f bytes
mscorlib.dll!System.Convert.ChangeType(object value, System.Type conversionType, System.IFormatProvider provider) + 0x1ff bytes
PresentationFramework.dll!MS.Internal.Data.SystemConvertConverter.Convert(object o, System.Type type, object parameter, System.Globalization.CultureInfo culture) + 0x11 bytes
PresentationFramework.dll!MS.Internal.Data.DynamicValueConverter.Convert(object value, System.Type targetType, object parameter, System.Globalization.CultureInfo culture) + 0x51 bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.Selector.VerifyEqual(object knownValue, System.Type knownType, object itemValue, MS.Internal.Data.DynamicValueConverter converter) + 0x64 bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.Selector.FindItemWithValue(object value, out int index) + 0x1f7 bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.Selector.SelectItemWithValue(object value) + 0x3e bytes
PresentationFramework.dll!System.Windows.Controls.Primitives.Selector.CoerceSelectedValue(System.Windows.DependencyObject d, object value) + 0x91 bytes
WindowsBase.dll!System.Windows.DependencyObject.ProcessCoerceValue(System.Windows.DependencyProperty dp, System.Windows.PropertyMetadata metadata, ref System.Windows.EntryIndex entryIndex, ref int targetIndex, ref System.Windows.EffectiveValueEntry newEntry, ref System.Windows.EffectiveValueEntry oldEntry, ref object oldValue, object baseValue, object controlValue, System.Windows.CoerceValueCallback coerceValueCallback, bool coerceWithDeferredReference, bool coerceWithCurrentValue, bool skipBaseValueChecks) + 0x55 bytes
WindowsBase.dll!System.Windows.DependencyObject.UpdateEffectiveValue(System.Windows.EntryIndex entryIndex, System.Windows.DependencyProperty dp, System.Windows.PropertyMetadata metadata, System.Windows.EffectiveValueEntry oldEntry, ref System.Windows.EffectiveValueEntry newEntry, bool coerceWithDeferredReference, bool coerceWithCurrentValue, System.Windows.OperationType operationType) + 0x247 bytes
WindowsBase.dll!System.Windows.DependencyObject.InvalidateProperty(System.Windows.DependencyProperty dp, bool preserveCurrentValue) + 0xd1 bytes
PresentationFramework.dll!System.Windows.StyleHelper.InvalidateDependents(System.Windows.Style ownerStyle, System.Windows.FrameworkTemplate frameworkTemplate, System.Windows.DependencyObject container, System.Windows.DependencyProperty dp, ref MS.Utility.FrugalStructList<System.Windows.ChildPropertyDependent> dependents, bool invalidateOnlyContainer) + 0x79 bytes
PresentationFramework.dll!System.Windows.StyleHelper.OnBindingValueInTemplateChanged(object sender, MS.Internal.Data.BindingValueChangedEventArgs e) + 0xe2 bytes
PresentationFramework.dll!System.Windows.Data.BindingExpressionBase.ChangeValue(object newValue, bool notify) + 0x94 bytes
PresentationFramework.dll!System.Windows.Data.BindingExpression.TransferValue(object newValue, bool isASubPropertyChange) + 0x40c bytes
PresentationFramework.dll!System.Windows.Data.BindingExpression.ScheduleTransfer(bool isASubPropertyChange) + 0x3a bytes
PresentationFramework.dll!MS.Internal.Data.ClrBindingWorker.NewValueAvailable(bool dependencySourcesChanged, bool initialValue, bool isASubPropertyChange) + 0x60 bytes
PresentationFramework.dll!MS.Internal.Data.PropertyPathWorker.UpdateSourceValueState(int k, System.ComponentModel.ICollectionView collectionView, object newValue, bool isASubPropertyChange) + 0x211 bytes
PresentationFramework.dll!MS.Internal.Data.ClrBindingWorker.OnSourcePropertyChanged(object o, string propName) + 0x85 bytes
PresentationFramework.dll!MS.Internal.Data.PropertyPathWorker.OnPropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e) + 0x68 bytes
WindowsBase.dll!System.Windows.WeakEventManager.ListenerList<System.ComponentModel.PropertyChangedEventArgs>.DeliverEvent(object sender, System.EventArgs e, System.Type managerType) + 0x12c bytes
WindowsBase.dll!System.ComponentModel.PropertyChangedEventManager.OnPropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs args) + 0x40c bytes
> MyApp.Framework.Core.dll!MyApp.Framework.Core.NotifyObject.RaisePropertyChanged(string propertyName) Line 45 + 0x32 bytes C#