Just discovered that you can set the currentTime for audio as long as the time is in seconds, not milliseconds.
(Could not delete the original question, so edited this post.)
Hi @Dee. Just edited your title to show it as solved so nobody thinks you’re being ignored 
Yeah, always currentTime is in seconds. setInterval() and setTimeout() methods are in milliseconds but these aren’t related to audio 
A good place to look is w3schools.com or developer.mozilla.org for properties and methods relating to Javascript and other languages.