diff --git a/format/rtmp/rtmp.go b/format/rtmp/rtmp.go
index 212ee06c..bfa27c1f 100644
--- a/format/rtmp/rtmp.go
+++ b/format/rtmp/rtmp.go
@@ -353,7 +353,7 @@ var CodecTypes = flv.CodecTypes
 
 func (self *Conn) writeBasicConf() (err error) {
 	// > SetChunkSize
-	if err = self.writeSetChunkSize(1024 * 1024 * 128); err != nil {
+	if err = self.writeSetChunkSize(1024 * 1024 * 10); err != nil {
 		return
 	}
 	// > WindowAckSize