Presto audio examples

Discussion Learning Resources
1

I’ve been playing around with the built in piezo speaker to play sound files albeit quiet. I think you need more power to get a better sounding audio.

There’s also a demo using duty cycle to change the volume of a simple tone.

2

It’s a bit of a bummer, IMHO, that it has a piezo instead of a speaker. I don’t own one, but have plans to buy one. I’ll likely try something like this with mine.
Adafruit STEMMA Speaker - Plug and Play Audio Amplifier

EDIT: Or this.
Speaker for micro:bit