Question

I’ve tried setting background audio through both a mediaElement in XAML

<MediaElement x:Name="MyAudio" Source="Assets/Sound.mp3" AudioCategory="BackgroundCapableMedia" AutoPlay="False" />

And programmatically

async void setUpAudio()
{
    var package = Windows.ApplicationModel.Package.Current;
    var installedLocation = package.InstalledLocation;
    var storageFile = await installedLocation.GetFileAsync("Assets\\Sound.mp3");
    if (storageFile != null)
    {
        var stream = await storageFile.OpenAsync(Windows.Storage.FileAccessMode.Read);
        _soundEffect = new MediaElement();
        _soundEffect.AudioCategory = AudioCategory.BackgroundCapableMedia;
        _soundEffect.AutoPlay = false;
        _soundEffect.SetSource(stream, storageFile.ContentType);
    }
}

// and later...
_soundEffect.Play();

But neither works for me. As soon as I minimise the app the music fades out

Answer 1

akton replied to a similar question with this excellent answer

It wasn’t easy to find initially as it doesn’t use ‘audio’ in the title and I wasn’t playing music. It’s an excellent, comprehensive answer, the likes of which I love to see on StackExchange. It also mentions a few things other answers to similar questions had failed to point out. In brief

• You need to handle the MediaControl events PlayPressed, PausePressed, PlayPausedTogglePressed and StopPressed, even if you have no buttons. EDIT: these events are required by Windows 8 app certification, make sure they actually work.
• Add audio to the list of support background tasks in the applications manifest [see aktons answer for more detail]

However, in implementing this solution I did come across what I can only assume is a bug. I’ve built a kitchen timer within a UserControl. It plays an optional ticking sound as it counts down and then buzzes when elapsed. However, if the ticking sound is turned off before the timer is set, the buzz sound will not play. It seems that a Windows 8 app needs to play a sound before being minimised in order for background audio to work. To fix this, I created a silent audio file which is 1 second in duration. This file plays whether the ticking is on or off. It’s a weird hack, and I hope I can figure out a better solution, but for now its all I can think of.