UWP custom toast notification sound doesn't play on mobile - notifications

Question

So I have an xml as notification body witch includes audio element with source (src) attribute pointing to preset windows sound and it doesn't play the sound I want and instead plays the default system sound. My notification xml looks like this (I use this as a test message to send trough Azure notification hubs debug option)
<?xml version="1.0" encoding="utf-8"?>
<toast>
<visual>
<binding template="ToastText01">
<text id="1">Test message</text>
</binding>
</visual>
<audio src="ms-winsoundevent:Notification.Looping.Alarm" loop="false"/>
</toast>
I don't have any toast handling on my app (no background task is launched or anything). Funny thing is that my PC plays the sound it should when it recieves the notification, but phone plays default sound every time.
I need to at least play preset windows sound, but playing custom sound from local files would be ace (this doesn't work with custom sounds neither). Also if you know if there's a possibility to start playing music from background task triggered by toast notification let me know, I couldn't find any info on google on this matter.
This is the microsoft link that tells my xml is good (even though it doesn't work): https://msdn.microsoft.com/en-us/library/windows/apps/br230842.aspx

Answer 1

I don't have any toast handling on my app (no background task is launched or anything). Funny thing is that my PC plays the sound it should when it recieves the notification, but phone plays default sound every time.
Looks like all values which prefix is ms-winsoundevent:Notification.Looping will be replaced by system sound while set loop element to false. Based on my understanding, this should be an expected result, these values are for Looping audio, if you need to disable looping, use the first 5 values, for example: ms-winsoundevent:Notification.IM
but playing custom sound from local files would be ace (this doesn't work with custom sounds neither)
This is a known issue which was mentioned in this article
The reason is path parser has an issue to resolve ms-appx:/// path, so the audio src will be regarded as Invalid, then the default sound will be played.
The workaround is copying your wav audio file programmatically to LocalFolder and using the "ms-appdata:///local/" protocol, for example:
private async void Button_Click(object sender, RoutedEventArgs e)
{
Windows.Storage.StorageFile audioFile = await Windows.Storage.StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets/sound.wav"));
Windows.Storage.StorageFolder localFolder = Windows.Storage.ApplicationData.Current.LocalFolder;
await audioFile.CopyAsync(localFolder);
AddNotification();
}
public void AddNotification()
{
ToastTemplateType toastTemplate = ToastTemplateType.ToastText02;
XmlDocument toastXml = ToastNotificationManager.GetTemplateContent(toastTemplate);
XmlNodeList toastTextElements = toastXml.GetElementsByTagName("text");
toastTextElements[0].AppendChild(toastXml.CreateTextNode("This is a Toast Message"));
IXmlNode toastNode = toastXml.SelectSingleNode("/toast");
((XmlElement)toastNode).SetAttribute("launch", "MainPage.xaml");
XmlElement audio = toastXml.CreateElement("audio");
audio.SetAttribute("src", "ms-appdata:///local/sound.wav"); //Here
toastNode.AppendChild(audio);
ToastNotification toast = new ToastNotification(toastXml);
ToastNotificationManager.CreateToastNotifier().Show(toast);
}