By itself Protogame only supports WAV, which is to be honest an outdated format. All platforms supported by Protogame can support either OGG or mp3, so I don’t get why only wav is supported by asset tool.
Basically https://github.com/RedpointGames/Protogame/blob/master/Protogame/Assets/Audio/AudioAssetCompiler.cs needs to be updated to use the MonoGame compilation APIs to compile the content into an XNB. Happy to accept a PR which does this.
Sorry but your Code have a ‘IAssetCompiler’ class.
without Access to this class the Code can not used!
The source code for Protogame is available here: https://github.com/RedpointGames/Protogame
If you’ve started with a template and you want to be able to edit the source code, open up a terminal, cd to the directory where your project is, and then run:
Protobuild.exe --swap-to-source Protogame
then after saving everything in Visual Studio:
Protobuild.exe --resync
When the solution reloads you should see all of the Protogame source code there and you can edit it as you like.