diff --git a/transport/internet/headers/srtp/srtp_test.go b/transport/internet/headers/srtp/srtp_test.go
index b959c8b1e..1b08dae4e 100644
--- a/transport/internet/headers/srtp/srtp_test.go
+++ b/transport/internet/headers/srtp/srtp_test.go
@@ -18,7 +18,7 @@ func TestSRTPWrite(t *testing.T) {
 
 	srtp := srtpRaw.(*SRTP)
 
-	payload := buf.NewSize(2048)
+	payload := buf.New()
 	payload.AppendSupplier(srtp.Write)
 	payload.Append(content)
 
diff --git a/transport/internet/headers/utp/utp_test.go b/transport/internet/headers/utp/utp_test.go
index 4736001da..a41480e2f 100644
--- a/transport/internet/headers/utp/utp_test.go
+++ b/transport/internet/headers/utp/utp_test.go
@@ -18,7 +18,7 @@ func TestUTPWrite(t *testing.T) {
 
 	utp := utpRaw.(*UTP)
 
-	payload := buf.NewSize(2048)
+	payload := buf.New()
 	payload.AppendSupplier(utp.Write)
 	payload.Append(content)
 
diff --git a/transport/internet/headers/wechat/wechat_test.go b/transport/internet/headers/wechat/wechat_test.go
index 6fde0bfd5..80185d1e2 100644
--- a/transport/internet/headers/wechat/wechat_test.go
+++ b/transport/internet/headers/wechat/wechat_test.go
@@ -17,7 +17,7 @@ func TestUTPWrite(t *testing.T) {
 
 	video := videoRaw.(*VideoChat)
 
-	payload := buf.NewSize(2048)
+	payload := buf.New()
 	payload.AppendSupplier(video.Write)
 
 	assert(payload.Len(), Equals, video.Size())