WebAudioTrack | use plugin that enables you to record and play | Audio Utils library

Right now I have two methods of sending a WAV file to the server. A user can directly upload said file, or make a recording on their microphone. Once the files are sent, they are processed in nigh the same way. The file is sent to S3, and can later be played by clicking on some link (which plays the file via audio = new Audio('https://S3.url'); audio.play()

When dealing with a file from the microphone:

• audio.play() seems to work. Everything in the audio object is identical (except for the URL itself), but the sound won't actually play through the speakers. On the other hand, for an uploaded file, the sound plays through the speakers.
• When I visit the URLs directly—both of them open up the sound-player (in Chrome) or prompt a download for a WAV file (in Firefox). The sound-player appropriately plays both sounds, and the downloaded WAV files each contain their respective sound, which other programs can play
• If I actually download the file with sound from the user's microphone instead of sending it directly to the server, then manually upload the WAV file, everything works as it should (as it would with any other uploaded WAV file).
• In any scenario where the microphone-sound is uploaded somewhere, then downloaded, it is downloaded as a WAV file and plays accordingly. Anything which uses the re-uploaded WAV file works as intended.

Here's how I'm getting the sound from the user's microphone. First, I use WebAudioTrack to place a record button on my webpage. Once the user stops their recording, they hit the submit button which runs: