diff --git a/qrenderdoc/Code/QRDUtils.cpp b/qrenderdoc/Code/QRDUtils.cpp
index fd598165d..adf0d910f 100644
--- a/qrenderdoc/Code/QRDUtils.cpp
+++ b/qrenderdoc/Code/QRDUtils.cpp
@@ -26,6 +26,7 @@
 #include <QGuiApplication>
 #include <QJsonDocument>
 #include <QMenu>
+#include <QMetaMethod>
 
 bool SaveToJSON(QVariantMap &data, QIODevice &f, const char *magicIdentifier, uint32_t magicVersion)
 {
@@ -88,6 +89,14 @@ bool LoadFromJSON(QVariantMap &data, QIODevice &f, const char *magicIdentifier,
   return true;
 }
 
+int GUIInvoke::methodIndex = -1;
+
+void GUIInvoke::init()
+{
+  GUIInvoke *invoke = new GUIInvoke();
+  methodIndex = invoke->metaObject()->indexOfMethod(QMetaObject::normalizedSignature("doInvoke()"));
+}
+
 void GUIInvoke::call(const std::function<void()> &f)
 {
   if(qApp->thread() == QThread::currentThread())
@@ -96,12 +105,9 @@ void GUIInvoke::call(const std::function<void()> &f)
     return;
   }
 
-  // TODO: could maybe do away with string compare here via caching
-  // invoke->metaObject()->indexOfMethod("doInvoke"); ?
-
   GUIInvoke *invoke = new GUIInvoke(f);
   invoke->moveToThread(qApp->thread());
-  QMetaObject::invokeMethod(invoke, "doInvoke", Qt::QueuedConnection);
+  invoke->metaObject()->method(methodIndex).invoke(invoke, Qt::QueuedConnection);
 }
 
 void GUIInvoke::blockcall(const std::function<void()> &f)
@@ -112,12 +118,9 @@ void GUIInvoke::blockcall(const std::function<void()> &f)
     return;
   }
 
-  // TODO: could maybe do away with string compare here via caching
-  // invoke->metaObject()->indexOfMethod("doInvoke"); ?
-
   GUIInvoke *invoke = new GUIInvoke(f);
   invoke->moveToThread(qApp->thread());
-  QMetaObject::invokeMethod(invoke, "doInvoke", Qt::BlockingQueuedConnection);
+  invoke->metaObject()->method(methodIndex).invoke(invoke, Qt::BlockingQueuedConnection);
 }
 
 void RDDialog::show(QMenu *menu, QPoint pos)
diff --git a/qrenderdoc/Code/QRDUtils.h b/qrenderdoc/Code/QRDUtils.h
index cf1507c88..55ac0fc69 100644
--- a/qrenderdoc/Code/QRDUtils.h
+++ b/qrenderdoc/Code/QRDUtils.h
@@ -55,9 +55,13 @@ class GUIInvoke : public QObject
 private:
   Q_OBJECT
   GUIInvoke(const std::function<void()> &f) : func(f) {}
+  GUIInvoke() {}
   std::function<void()> func;
 
+  static int methodIndex;
+
 public:
+  static void init();
   static void call(const std::function<void()> &f);
   static void blockcall(const std::function<void()> &f);
 
diff --git a/qrenderdoc/Code/qrenderdoc.cpp b/qrenderdoc/Code/qrenderdoc.cpp
index f990742bb..8bee1c9f2 100644
--- a/qrenderdoc/Code/qrenderdoc.cpp
+++ b/qrenderdoc/Code/qrenderdoc.cpp
@@ -132,6 +132,8 @@ int main(int argc, char *argv[])
 
     config.SetupFormatting();
 
+    GUIInvoke::init();
+
     CaptureContext ctx(filename, remoteHost, remoteIdent, temp, config);
 
     while(ctx.isRunning())