WP7 Custom Pivot control flickering

Since there is no Border.Effect property in Silverlight for Windows Phone, I managed to recreate a similar effect. What came up after editing the stile of a Pivot control is this:

As you can see the project is one of Visual Studio default templates. With my custom style, the ItemsPanel is behind that black/gray gradient so, when you scroll the list, it's like items are disappearing.

<Style x:Key="PivotStyle1" TargetType="controls:Pivot">
            <Setter Property="Margin" Value="0"/>
            <Setter Property="Padding" Value="0"/>
            <Setter Property="Foreground" Value="{StaticResource PhoneForegroundBrush}"/>
            <Setter Property="Background" Value="Transparent"/>
            <Setter Property="ItemTemplate">
                <Setter.Value>
                    <DataTemplate>
                        <ItemsPanelTemplate>
                            <Grid />
                        </ItemsPanelTemplate>
                    </DataTemplate>
                </Setter.Value>
            </Setter>
            <Setter Property="Template">
                <Setter.Value>
                    <ControlTemplate TargetType="controls:Pivot">
                        <Grid HorizontalAlignment="{TemplateBinding HorizontalAlignment}" VerticalAlignment="{TemplateBinding VerticalAlignment}">
                            <Grid.RowDefinitions>
                                <RowDefinition Height="70" />
                                <RowDefinition Height="Auto" />
                            </Grid.RowDefinitions>
                            <Grid Background="{TemplateBinding Background}" CacheMode="BitmapCache" Grid.RowSpan="3"/>

                            <Grid Grid.Row="1">
                                <ItemsPresenter x:Name="PivotItemPresenter" Margin="{TemplateBinding Padding}" VerticalAlignment="Top"/>

                                <Grid Height="50" VerticalAlignment="Top">
                                    <Grid.Background>
                                        <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                            <GradientStop Color="#66000000" Offset="0"/>
                                            <GradientStop Offset="1"/>
                                            <GradientStop Color="#19000000" Offset="0.523"/>
                                        </LinearGradientBrush>
                                    </Grid.Background>
                                </Grid>
                            </Grid>



                            <Grid Height="70" Grid.Row="0" VerticalAlignment="Top">
                                <Grid.Background>
                                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                        <GradientStop Color="#FF1665CD" Offset="1"/>
                                        <GradientStop Color="#FF5395EC"/>
                                    </LinearGradientBrush>
                                </Grid.Background>
                                <Primitives:PivotHeadersControl x:Name="HeadersListElement"/>
                            </Grid>

                        </Grid>
                    </ControlTemplate>
                </Setter.Value>
            </Setter>
        </Style>

The problem is that whenever I slide towards PivotItems the two Grid with a gradient background flicker. What could be the problem?

UPDATE: The flickering only appears when I navigate back to this page

Solved setting CacheMode to the Grid elements. For Example:

<Grid Height="70" CacheMode="BitmapCache" Grid.Row="0" VerticalAlignment="Top">
                                <Grid.Background>
                                    <LinearGradientBrush EndPoint="0.5,1" StartPoint="0.5,0">
                                        <GradientStop Color="#FF1665CD" Offset="1"/>
                                        <GradientStop Color="#FF5395EC"/>
                                    </LinearGradientBrush>
                                </Grid.Background>
                                <Primitives:PivotHeadersControl x:Name="HeadersListElement"/>
                            </Grid>