From 162e7882df542a4c4fd4b557ef1336030f1c2c67 Mon Sep 17 00:00:00 2001
From: OrlandoCo <luisorlando.co@gmail.com>
Date: Wed, 9 Dec 2020 10:13:18 -0600
Subject: [PATCH] fix(sfu): write correct ssrc for buffered packets

---
 pkg/buffer/interceptor.go | 3 ++-
 pkg/sfu/router.go         | 1 +
 2 files changed, 3 insertions(+), 1 deletion(-)

diff --git a/pkg/buffer/interceptor.go b/pkg/buffer/interceptor.go
index 91d2b9495..f336d7617 100644
--- a/pkg/buffer/interceptor.go
+++ b/pkg/buffer/interceptor.go
@@ -90,7 +90,7 @@ func (i *Interceptor) BindRTCPWriter(writer interceptor.RTCPWriter) interceptor.
 	return writer
 }
 
-func (i *Interceptor) GetBufferedPackets(ssrc uint32, snOffset uint16, tsOffset uint32, sn []uint16) []rtp.Packet {
+func (i *Interceptor) GetBufferedPackets(ssrc, mediaSSRC uint32, snOffset uint16, tsOffset uint32, sn []uint16) []rtp.Packet {
 	buffer := i.getBuffer(ssrc)
 	if buffer == nil {
 		return nil
@@ -101,6 +101,7 @@ func (i *Interceptor) GetBufferedPackets(ssrc uint32, snOffset uint16, tsOffset
 		if err != nil {
 			continue
 		}
+		h.SSRC = mediaSSRC
 		h.SequenceNumber -= snOffset
 		h.Timestamp -= tsOffset
 		pkts = append(pkts, rtp.Packet{
diff --git a/pkg/sfu/router.go b/pkg/sfu/router.go
index 463987706..b51fc0909 100644
--- a/pkg/sfu/router.go
+++ b/pkg/sfu/router.go
@@ -204,6 +204,7 @@ func (r *router) loopDownTrackRTCP(track *DownTrack) {
 				for _, pair := range p.Nacks {
 					for _, pt := range r.buffer.GetBufferedPackets(
 						track.receiver.SSRC(track.currentSpatialLayer),
+						track.ssrc,
 						track.snOffset,
 						track.tsOffset,
 						track.nList.getNACKSeqNo(pair.PacketList())) {