diff --git a/stream/mts/encoder.go b/stream/mts/encoder.go
index decc8558..60393285 100644
--- a/stream/mts/encoder.go
+++ b/stream/mts/encoder.go
@@ -233,6 +233,12 @@ const (
 // generate handles the incoming data and generates equivalent mpegts packets -
 // sending them to the output channel.
 func (e *Encoder) Encode(nalu []byte) error {
+	if e.psiCount <= 0 {
+		err := e.writePSI()
+		if err != nil {
+			return err
+		}
+	}
 	// Prepare PES data.
 	pesPkt := pes.Packet{
 		StreamID:     streamID,
@@ -262,14 +268,8 @@ func (e *Encoder) Encode(nalu []byte) error {
 			pkt.PCR = e.pcr()
 			pusi = false
 		}
-		if e.psiCount <= 0 {
-			err := e.writePSI()
-			if err != nil {
-				return err
-			}
-		}
-		e.psiCount--
 		_, err := e.dst.Write(pkt.Bytes(e.tsSpace[:PacketSize]))
+		e.psiCount--
 		if err != nil {
 			return err
 		}