[Zubersoft]

MIDI files can be played as audio in the Android version, but not in the Windows 10 version. It does matter which format you are trying to add though. MobileSheetsPro supports the following audio file types:

• .mp3
  
• .mp4
  
• .m4a
  
• .aac
  
• .flac
  
• .ogg
  
• .mkv
  
• .3gp
  
• .ts
  
• .mid
  
• .xmf
  
• .mxmf
  
• .rtttl
  
• .rtx
  
• .ota
  
• .imy
  
• .wav
  
• .wma
  

Only .mp3 files work with the advanced audio features such as pitch shifting and tempo adjustments though.

Mike