Lock screen subtitle is always "unknown" in Samsung S10+

### Device

Samsung S10+ running Android 11

## 🐛 Bug Report

On lock screen the subtitle is always shown as **"unknown"**. Not able to change that so far with my various attempts. Its not using any of the media item metadata, so not sure where its pulling that text from.

### Expected behavior

The notification subtitle should have a meaningful text from metadata of the mp3 file

### Reproduction steps

Please find [sample repository](https://github.com/justcoding121/xamarin-sandbox) here to reproduce this issue. The repository is just a basic single page Xamarin.Forms app created with visual studio 2019.

Relevant code added to the default blank app is in below two lines, result is shown in screenshot above.

https://github.com/justcoding121/xamarin-sandbox/blob/main/Xamarin.SandboxApp/Xamarin.SandboxApp/Xamarin.SandboxApp.Android/MainActivity.cs#L26

https://github.com/justcoding121/xamarin-sandbox/blob/main/Xamarin.SandboxApp/Xamarin.SandboxApp/Xamarin.SandboxApp/MainPage.xaml.cs#L19

### Configuration

**Version:** 1.0.8

**Platform:**
- [ ] :iphone: iOS
- [X] :robot: Android
- [ ] :checkered_flag: WPF
- [ ] :earth_americas: UWP
- [ ] :apple: MacOS
- [ ] :tv: tvOS
- [ ] :monkey: Xamarin.Forms