commit - 2e4d2483483becc6c7c2bb0350b3693ad7382931
commit + 8d2c4bc42dfbbe01d8d7cfd968ca60c8048ae6f9
blob - 1abec638603b1258b5b271e7b67ac3d4c8d89408
blob + b20753e126a9a891a97135477202fa0023f80a73
--- cmd/autx/autx.go
+++ cmd/autx/autx.go
@@ -53,7 +53,7 @@ func main() {
 	if err != nil {
 		log.Fatal(err)
 	}
-	session.Clock = 44100 // 44.1KHz, not the audio sample rate.
+	session.Clock = rtp.ClockPCMAudio // not the audio sample rate.
 
 	origin := sdp.Origin{
 		ID:      sdp.Now(),
blob - 35e9c24be1626b1d6c22d5e77bd4823714ec8284
blob + 5c634bae8a2f1f60af2fdb497a11d8d56b6f94fc
--- rtp/rtp.go
+++ rtp/rtp.go
@@ -80,9 +80,9 @@ const (
 type PayloadType uint8
 
 const (
-	PayloadL16Stereo  PayloadType = 10
-	PayloadL16Mono PayloadType = 11
-	PayloadMP2T PayloadType = 33
+	PayloadL16Stereo PayloadType = 10
+	PayloadL16Mono   PayloadType = 11
+	PayloadMP2T      PayloadType = 33
 	// ...
 )
 
@@ -103,13 +103,16 @@ func (t PayloadType) String() string {
 	switch t {
 	case PayloadMP2T:
 		return "MP2T"
+	case PayloadL16Stereo, PayloadL16Mono:
+		return fmt.Sprintf("%d", t)
 	}
 	return "unknown"
 }
 
 const (
-	ClockMP2T = 90000 // 90KHz
-	ClockText = 1000  // 1KHz
+	ClockMP2T     = 90000 // 90KHz
+	ClockPCMAudio = 44100 // 44.1KHz
+	ClockText     = 1000  // 1KHz
 )
 
 type Extension struct {
blob - 1161b17c48b0bd96c491b61826708adbc5220058
blob + a2f6d52965ac0aa8362e39972003ca2ce9e7d658
--- sdp/example_test.go
+++ sdp/example_test.go
@@ -27,10 +27,10 @@ func Example() {
 				Type:      sdp.MediaTypeAudio,
 				Port:      6969,
 				Transport: sdp.ProtoRTP,
-				Format:    []string{fmt.Sprintf("%d", rtp.PayloadL16Mono)},
+				Format:    []string{rtp.PayloadL16Mono.String()},
 				Attributes: []string{
-					fmt.Sprintf("rtpmap:%d", rtp.PayloadL16Mono),
-					fmt.Sprintf("L16/%d", 22050),
+					"rtpmap:" + rtp.PayloadL16Mono.String(),
+					"L16/22050",
 				},
 			},
 		},