Change codec channels from uint16 to uint8

pkg/core/codec.go

@@ -13,7 +13,7 @@ import (
 type Codec struct {
 	Name        string // H264, PCMU, PCMA, opus...
 	ClockRate   uint32 // 90000, 8000, 16000...
-	Channels    uint16 // 0, 1, 2
+	Channels    uint8  // 0, 1, 2
 	FmtpLine    string
 	PayloadType uint8
 }

pkg/core/media.go

@@ -139,7 +139,7 @@ func MarshalSDP(name string, medias []*Media) ([]byte, error) {
 				Protos: []string{"RTP", "AVP"},
 			},
 		}
-		md.WithCodec(codec.PayloadType, name, codec.ClockRate, codec.Channels, codec.FmtpLine)
+		md.WithCodec(codec.PayloadType, name, codec.ClockRate, uint16(codec.Channels), codec.FmtpLine)
 
 		if media.Direction != "" {
 			md.WithPropertyAttribute(media.Direction)