diff --git a/params_test.go b/params_test.go
index ddfa329..9bc8a18 100644
--- a/params_test.go
+++ b/params_test.go
@@ -388,6 +388,12 @@ func TestSetParameter(t *testing.T) {
 			msg.Set(field, value)
 			return msg
 		}(),
+	}, {
+		fields: "double_list",
+		value:  "1.234",
+		want: &testv1.ParameterValues{
+			DoubleList: []float64{1.234},
+		},
 	}, {
 		fields:  "unknownField",
 		value:   "hello",
diff --git a/transcoder.go b/transcoder.go
index 0795038..bcd5068 100644
--- a/transcoder.go
+++ b/transcoder.go
@@ -1494,7 +1494,7 @@ func (w *envelopingWriter) maybeInit() {
 	var env envelope
 	env.compressed = w.rw.op.client.respCompression != nil
 	env.length = uint32(w.rw.contentLen)
-	envBytes := w.rw.op.clientEnveloper.encodeEnvelope(envelope{})
+	envBytes := w.rw.op.clientEnveloper.encodeEnvelope(env)
 	_, err := w.w.Write(envBytes[:])
 	if err != nil {
 		w.err = err