From 831d76c10e7bf036766691e7555ecab0bb777cfc Mon Sep 17 00:00:00 2001
From: Kibi Kelburton <git@f0ck.it>
Date: Mon, 23 Feb 2026 04:11:46 +0100
Subject: [PATCH] maybe this fixes the poor audio idk loool

---
 public/viewer.js | 37 ++++++++++++++++++++++++++++++-------
 1 file changed, 30 insertions(+), 7 deletions(-)

diff --git a/public/viewer.js b/public/viewer.js
index 5eb7564..e7f304a 100644
--- a/public/viewer.js
+++ b/public/viewer.js
@@ -23,12 +23,12 @@ socket.on('offer', (id, description) => {
         overlay.classList.add('hidden');
     };
 
-    // Auto-unmute when the user interacts with the document to bypass browser// Auto-unmute when the user interacts with the document to bypass browser
-document.addEventListener('click', () => {
-    remoteVideo.muted = false;
-    // Set sink to max possible volume explicitly avoiding browser gain staging
-    remoteVideo.volume = 1.0; 
-}, {once: true});
+    // Auto-unmute when the user interacts with the document to bypass browser autoplay restrictions
+    document.addEventListener('click', () => {
+        remoteVideo.muted = false;
+        // Set sink to max possible volume explicitly avoiding browser gain staging
+        remoteVideo.volume = 1.0; 
+    }, {once: true});
 
     peerConnection.onicecandidate = event => {
         if (event.candidate) {
@@ -39,7 +39,30 @@ document.addEventListener('click', () => {
     peerConnection
         .setRemoteDescription(description)
         .then(() => peerConnection.createAnswer())
-        .then(sdp => peerConnection.setLocalDescription(sdp))
+        .then(sdp => {
+            let sdpLines = sdp.sdp.split('\r\n');
+            let opusPayloadType = null;
+            for (let i = 0; i < sdpLines.length; i++) {
+                if (sdpLines[i].includes('a=rtpmap:') && sdpLines[i].includes('opus/48000/2')) {
+                    const match = sdpLines[i].match(/a=rtpmap:(\d+) /);
+                    if (match) opusPayloadType = match[1];
+                }
+            }
+            if (opusPayloadType) {
+                let fmtpFound = false;
+                for (let i = 0; i < sdpLines.length; i++) {
+                    if (sdpLines[i].startsWith(`a=fmtp:${opusPayloadType}`)) {
+                        sdpLines[i] = `a=fmtp:${opusPayloadType} minptime=10;useinbandfec=1;maxplaybackrate=48000;stereo=1;sprop-stereo=1;maxaveragebitrate=510000;cbr=1`;
+                        fmtpFound = true;
+                    }
+                }
+                if (!fmtpFound) {
+                    sdpLines.push(`a=fmtp:${opusPayloadType} minptime=10;useinbandfec=1;maxplaybackrate=48000;stereo=1;sprop-stereo=1;maxaveragebitrate=510000;cbr=1`);
+                }
+            }
+            sdp.sdp = sdpLines.join('\r\n');
+            return peerConnection.setLocalDescription(sdp);
+        })
         .then(() => {
             socket.emit('answer', id, peerConnection.localDescription);
         });