diff --git a/pkg/sfu/buffer/rtpstats_sender.go b/pkg/sfu/buffer/rtpstats_sender.go
index 3bcf8cc48..c67f6099d 100644
--- a/pkg/sfu/buffer/rtpstats_sender.go
+++ b/pkg/sfu/buffer/rtpstats_sender.go
@@ -146,7 +146,7 @@ func (r *RTPStatsSender) Update(
 		r.highestTime = packetTime
 
 		r.extStartSN = extSequenceNumber
-		r.extHighestSN = extSequenceNumber
+		r.extHighestSN = extSequenceNumber - 1
 
 		r.extStartTS = extTimestamp
 		r.extHighestTS = extTimestamp