It's an issue with Godot on the web unfortunately, when you're dropping frames the audio starts clipping and crackling. Judging by the other comment, the lua integration must be doing some heavy work.
Same for me, when the code is not correct, the music is much slower and very crackly. Once the code gives the correct solution, the music speeds up and the crackles go away.
popcar2|7 months ago
yardshop|7 months ago
yardshop|7 months ago
Also agreed, very fun!