Playing .ogg files made in Audacity, either by code or by frame script, does not work. I verified that the sound file is valid (tested it in Groove Music) and that I typed the correct name.
playSound("music_title.ogg"); I tried a .wav sound and it worked.
Edit: .mp3s also work.
Also, if you attach a sound to a Button’s 3rd frame, it will play its sound automatically (not what you want, since it’s a click sound) unless you run stop() on it in Default().