not playing audio from buffer stored in the database - blob

Question

I've spent 2 days with this thing and couldn't find a solution but seems like im getting closer. The goal is to record audio in the browser and store in the the database and get it whenever i need it.
I encoded the audio to base64 and sent it to the server stored as binary in the mongodb, created a get route in which i find the audio by id and send the buffer via res.send() along with the content type set to audio/webm (default mime type)
but the thing is I'm getting this blank video, seems like it's not knowing how to decode it or something. There might be something wrong with the content type.
navigator.mediaDevices.getUserMedia({ audio: true, video: false })
.then((mediaRecorderObj) => {
let mediaRecorder = new MediaRecorder(mediaRecorderObj, { mimType: 'audio/webm;base64' })
const m = mediaRecorder;
let chunk = []
startBtn.addEventListener('click', () => {
mediaRecorder.start()
console.log('started recording..');
})
endBtn.addEventListener('click', () => {
mediaRecorder.stop()
console.log('just stopped recording');
})
//-----When Data Is Available
mediaRecorder.ondataavailable = (e) => {
chunk.push(e.data);
}
//--------When finished adding it to chunk
mediaRecorder.onstop = () => {
const blob = new Blob(chunk, { 'type': 'audio/webm' })
chunk = []
const reader = new FileReader()
reader.readAsDataURL(blob)
reader.onloadend = async () => {
const buffer = reader.result
const bodyObj = {
voice: buffer
}
await fetch('http://localhost:3000/upload-spoken-bio', {
method: 'post',
body: JSON.stringify(bodyObj),
headers: { 'Content-Type': 'application/json' }
})
}
}
})
and this is the server side
//----------Upload
spokenBio.post('/upload-spoken-bio', async (req, res) => {
const buffer = req.body
try {
const newBuffer = new SpokenCon(buffer)
await newBuffer.save()
}
catch (err) {
console.log(err.message);
}
})
//----------Retrieve
spokenBio.get('/get-spoken-bio/:id', async (req, res) => {
const id = req.params.id
try {
const field = await SpokenCon.findById(id)
const binary = field.voice
res.set({ 'Content-Type': 'audio/webm' })
res.send(binary)
}
catch (err) {
console.log(err.message);
}
})