diff --git a/codec.go b/codec.go
index 44f16d5..70ef0b9 100644
--- a/codec.go
+++ b/codec.go
@@ -116,10 +116,12 @@ func (jsonCodec) Marshal(v interface{}) ([]byte, error) {
 }
 
 func (jsonCodec) Unmarshal(data []byte, v interface{}) error {
+	if len(data) == 0 {
+		return nil
+	}
 	if pb, ok := v.(proto.Message); ok {
 		return jsonpb.Unmarshal(b.NewReader(data), pb)
 	}
-
 	return json.Unmarshal(data, v)
 }
 
diff --git a/grpc.go b/grpc.go
index e8e23a3..3d158ea 100644
--- a/grpc.go
+++ b/grpc.go
@@ -207,7 +207,7 @@ func (g *grpcClient) stream(ctx context.Context, node *registry.Node, req client
 		ServerStreams: true,
 	}
 
-	grpcCallOptions := []grpc.CallOption{}
+	grpcCallOptions := []grpc.CallOption{grpc.CallContentSubtype(cf.Name())}
 	if opts := g.getGrpcCallOptions(); opts != nil {
 		grpcCallOptions = append(grpcCallOptions, opts...)
 	}