WPF 按钮背景图片切换,该如何处理

WPF 按钮背景图片切换
我做的是一个播放器，然后放置了一个按钮，按钮的作用是静音。想要点击按钮实现静音的同时，背景图片切换成静音的图片。找了很多方法还是没有实现。大神们帮帮忙啊！！！！

------解决思路----------------------

<Style  TargetType="{x:Type Button}">

            <Setter Property ="GroupName" Value="SelectTicket"/>

            <Setter Property="Height" Value="40"></Setter>

            <Setter Property="Width" Value="60"></Setter>

            <Setter Property="FontSize" Value="18"></Setter>

            <Setter Property="Template">

                <Setter.Value>

                    <ControlTemplate TargetType="{x:Type Button}">

                        <Border x:Name="ContentContainer"  Width="{TemplateBinding Width}" Height="{TemplateBinding Height}" SnapsToDevicePixels="True" BorderBrush="Transparent"  

                            BorderThickness="0" VerticalAlignment="Center" HorizontalAlignment="Stretch" CornerRadius="2">

                            <TextBlock Text="{TemplateBinding Content}" Foreground="White"   VerticalAlignment="Center"  TextAlignment="Center" HorizontalAlignment="Center"/>

                            <Border.Background>

                                <ImageBrush ImageSource="/Images/Background.png"/>

                            </Border.Background>

                        </Border>

                        <ControlTemplate.Triggers>

                            <Trigger  Property="IsMouseOver"  Value="True">

                                <Setter Property="Background" TargetName="ContentContainer">

                                    <Setter.Value>

                                        <ImageBrush ImageSource="/Images/PressBg.png"/>

                                    </Setter.Value>

                                </Setter>

                            </Trigger>

                        </ControlTemplate.Triggers>

                    </ControlTemplate>

                </Setter.Value>

            </Setter>

        </Style>

Background.png 与 PressBg.png  都是作为 内容  嵌入到 Image文件夹下
------解决思路----------------------
 <Setter Property ="GroupName" Value="SelectTicket"/>

 把这个去掉。
------解决思路----------------------
1：设置 style的Key值       也就是 x:Key=""  具体一个名字，然后在Button 的xaml 上使用staticresource引用。具体去搜索用法
２：Property　　设置成其它事件，比如IsFocused 等， 了解 WPF 触发器