Just for fun and to see how it works, I made a recorder using H5P. It only saves .wav files, so I made a change to allow those now as uploads.
Note, this appears to not be working, it is generating an HTTPS error, leaving it here for testing and reporting… As it turns out, the Discourse platform strips out the necessary portion of the embed code that triggers a request to access the microphone. Until further notice, I refer anyone interested in the same H5P recorder in use here.