Multimedia w WPF: odtwarzanie dźwięku i wideo

<ItemGroup>
  <Content Include="Media\Video\prezentacja.mp4">
    <CopyToOutputDirectory>Always</CopyToOutputDirectory>
  </Content>
</ItemGroup>

<Window x:Class="AVWpfApp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        Title="Odtwarzacz" Height="340" Width="450">
    <StackPanel Margin="20">
        <MediaElement x:Name="Odtwarzacz"
                      Source="Media/Video/prezentacja.mp4"
                      LoadedBehavior="Manual"
                      Height="180" />

        <StackPanel Orientation="Horizontal" HorizontalAlignment="Center" Margin="0,10,0,0">
            <Button Content="Play" Width="80" Margin="5" Click="Play_Click" />
            <Button Content="Pauza" Width="80" Margin="5" Click="Pauza_Click" />
            <Button Content="Stop" Width="80" Margin="5" Click="Stop_Click" />
        </StackPanel>

        <Slider x:Name="SuwakGlosnosci" Minimum="0" Maximum="1" Value="0.5"
                ValueChanged="SuwakGlosnosci_ValueChanged" Margin="0,10,0,0" />
        <TextBlock x:Name="EtykietaPozycja" Text="00:00" HorizontalAlignment="Center" Margin="0,5,0,0" />
    </StackPanel>
</Window>

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Threading;

namespace AVWpfApp;

public partial class MainWindow : Window
{
    private readonly DispatcherTimer _zegar = new DispatcherTimer { Interval = TimeSpan.FromSeconds(1) };

    public MainWindow()
    {
        InitializeComponent();
        Odtwarzacz.Volume = SuwakGlosnosci.Value;

        _zegar.Tick += (s, e) => EtykietaPozycja.Text = Odtwarzacz.Position.ToString(@"mm\:ss");
        _zegar.Start();
    }

    private void Play_Click(object sender, RoutedEventArgs e)
    {
        Odtwarzacz.Play();
    }

    private void Pauza_Click(object sender, RoutedEventArgs e)
    {
        Odtwarzacz.Pause();
    }

    private void Stop_Click(object sender, RoutedEventArgs e)
    {
        Odtwarzacz.Stop();
    }

    private void SuwakGlosnosci_ValueChanged(object sender, RoutedPropertyChangedEventArgs<double> e)
    {
        if (Odtwarzacz != null)
        {
            Odtwarzacz.Volume = SuwakGlosnosci.Value;   // od 0 (cisza) do 1 (pełna głośność)
        }
    }
}