diff --git a/internal/midi.c b/internal/midi.c
index ef50026..04c9dd1 100644
--- a/internal/midi.c
+++ b/internal/midi.c
@@ -244,6 +244,7 @@ JSC_CCALL(midi_parse,
   JS_ROOT(evt, JS_NULL);
   int idx = 0;
 
+  JSValue tmp;
   for (tml_message *msg = midi; msg; msg = msg->next) {
     evt.val = JS_NewObject(js);
     JS_SetPropertyStr(js, evt.val, "time", JS_NewInt32(js, msg->time));
@@ -251,29 +252,35 @@ JSC_CCALL(midi_parse,
 
     switch (msg->type) {
       case TML_NOTE_ON:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "note_on"));
+        tmp = JS_NewString(js, "note_on");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "key", JS_NewInt32(js, msg->key));
         JS_SetPropertyStr(js, evt.val, "velocity", JS_NewInt32(js, msg->velocity));
         break;
       case TML_NOTE_OFF:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "note_off"));
+        tmp = JS_NewString(js, "note_off");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "key", JS_NewInt32(js, msg->key));
         break;
       case TML_CONTROL_CHANGE:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "control"));
+        tmp = JS_NewString(js, "control");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "control", JS_NewInt32(js, msg->control));
         JS_SetPropertyStr(js, evt.val, "value", JS_NewInt32(js, msg->control_value));
         break;
       case TML_PROGRAM_CHANGE:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "program"));
+        tmp = JS_NewString(js, "program");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "program", JS_NewInt32(js, msg->program));
         break;
       case TML_PITCH_BEND:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "pitch_bend"));
+        tmp = JS_NewString(js, "pitch_bend");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "pitch_bend", JS_NewInt32(js, msg->pitch_bend));
         break;
       case TML_SET_TEMPO:
-        JS_SetPropertyStr(js, evt.val, "type", JS_NewString(js, "tempo"));
+        tmp = JS_NewString(js, "tempo");
+        JS_SetPropertyStr(js, evt.val, "type", tmp);
         JS_SetPropertyStr(js, evt.val, "tempo", JS_NewInt32(js, tml_get_tempo_value(msg)));
         break;
       default: