I normally recommend to look into web audio API instead of trying different JS libraries because everything is basically a wrapper of the native API. I think this would help: AudioBuffer - Web APIs | MDN
for upload you can also use drag and drop: dragOver and dragLeave do not work - #6 by micuat
and for saving a file: wavefile - npm
if it’s more like a batch operation (if you know start/end time to trim) you can also consider editing on the server - which may be easier but has less flexibility on the editing.