diff --git a/format/rtmp/rtmp.go b/format/rtmp/rtmp.go
index 857271d..b1d9a68 100644
--- a/format/rtmp/rtmp.go
+++ b/format/rtmp/rtmp.go
@@ -1570,7 +1570,7 @@ func (self *Conn) handshakeServer() (err error) {
 	C2 := C0C1C2[1536+1:]
 
 	S0S1S2 := random[1536*2+1:]
-	//S0 := S0S1S2[:1]
+	S0 := S0S1S2[:1]
 	S1 := S0S1S2[1:1536+1]
 	S0S1 := S0S1S2[:1536+1]
 	S2 := S0S1S2[1536+1:]
@@ -1584,6 +1584,8 @@ func (self *Conn) handshakeServer() (err error) {
 		return
 	}
 
+	S0[0] = 3
+
 	clitime := pio.GetU32BE(C1[0:4])
 	srvtime := clitime
 	srvver := uint32(0x0d0e0a0d)