AudioListener error when mouse is moved outside canvas

I'm not sure whether this qualifies as a babylon.js bug, but here's my scenario:

• I'm embedding a babylon.js canvas in a WordPress page
• there's some audio in the scene, but no positional audio
• when the mouse is outside the canvas when the canvas loads, and the user moves the mouse, this error is thown, and the canvas crashes:

Uncaught TypeError: Failed to execute 'setPosition' on 'AudioListener': The provided float value is non-finite.
    at i._updateAudioParameters (babylon.custom.js:14)
    at i.render (babylon.custom.js:14)
    at main.js?v=201806111547:595
    at n._renderLoop (babylon.custom.js:6)

You can see it happen here: https://studio.rocketclowns.com/agnes/babylon-test/

Same result in Edge, Chrome and Firefox.

Help

Edit: I'm on Windows 10 and babylon.js is version 3.2.0.