From fc5d4438f85dd763336a0527ffcc73e518b10e82 Mon Sep 17 00:00:00 2001
From: Yukine <blazylp@gmail.com>
Date: Sat, 23 Dec 2017 12:29:06 +0100
Subject: [PATCH] backporting the fix for RTP header extensions (#2185)

---
 src/client/voice/receiver/VoiceReceiver.js | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/client/voice/receiver/VoiceReceiver.js b/src/client/voice/receiver/VoiceReceiver.js
index c568c6aed..13af9764a 100644
--- a/src/client/voice/receiver/VoiceReceiver.js
+++ b/src/client/voice/receiver/VoiceReceiver.js
@@ -161,6 +161,25 @@ class VoiceReceiver extends EventEmitter {
       return;
     }
     data = Buffer.from(data);
+
+    // Strip RTP Header Extensions (one-byte only)
+    if (data[0] === 0xBE && data[1] === 0xDE && data.length > 4) {
+      const headerExtensionLength = data.readUInt16BE(2);
+      let offset = 4;
+      for (let i = 0; i < headerExtensionLength; i++) {
+        const byte = data[offset];
+        offset++;
+        if (byte === 0) {
+          continue;
+        }
+        offset += 1 + (0b1111 & (byte >> 4));
+      }
+      while (data[offset] === 0) {
+        offset++;
+      }
+      data = data.slice(offset);
+    }
+
     if (this.opusStreams.get(user.id)) this.opusStreams.get(user.id)._push(data);
     /**
      * Emitted whenever voice data is received from the voice connection. This is _always_ emitted (unlike PCM).