disable audio gain processing and prefer H264

public/app.js

@@ -156,6 +156,26 @@ function preferOpus(pc) {
   }
 }
 
+function preferH264(pc) {
+  const capabilities = globalThis.RTCRtpReceiver?.getCapabilities?.('video');
+  const codecs = capabilities?.codecs || [];
+  const rank = (codec) => {
+    const mime = codec.mimeType?.toLowerCase() || '';
+    if (mime === 'video/h264') return 0;
+    if (mime === 'video/vp8') return 1;
+    if (mime === 'video/vp9') return 2;
+    return 3;
+  };
+  const ordered = [...codecs].sort((a, b) => rank(a) - rank(b));
+  for (const transceiver of pc.getTransceivers()) {
+    if (transceiver.receiver?.track?.kind === 'video' || transceiver.sender?.track?.kind === 'video') {
+      try { transceiver.setCodecPreferences(ordered); } catch (err) {
+        captureRumIssue('Could not prefer H.264 video codec', 'WARNING', { error: err?.message || String(err) });
+      }
+    }
+  }
+}
+
 function monitorPeerQuality(peer) {
   if (peer.qualityTimer) clearInterval(peer.qualityTimer);
   peer.qualityTimer = setInterval(async () => {
@@ -265,8 +285,8 @@ function effectiveIce() {
 function microphoneConstraints(deviceId = localStorage.getItem(LS_AUDIO_INPUT)) {
   const audio = {
     echoCancellation: true,
-    noiseSuppression: true,
+    noiseSuppression: false,
-    autoGainControl: true,
+    autoGainControl: false,
     channelCount: 1,
     sampleRate: 48000,
     sampleSize: 16,
@@ -1029,6 +1049,7 @@ function addScreenToPeer(peer) {
     }
     peerSenders.set(streamId, senders);
   }
+  preferH264(peer.pc);
   S.screenSenders.set(peer.id, peerSenders); // renegotiation fires automatically
 }