diff --git a/source/backend/CarlaStandalone.cpp b/source/backend/CarlaStandalone.cpp
index 0fae4c10b..8c40e4967 100644
--- a/source/backend/CarlaStandalone.cpp
+++ b/source/backend/CarlaStandalone.cpp
@@ -458,7 +458,7 @@ bool carla_engine_close(CarlaHostHandle handle)
 
 void carla_engine_idle(CarlaHostHandle handle)
 {
-    CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr,);
+    CARLA_SAFE_ASSERT_RETURN(handle->engine != nullptr && handle->isStandalone,);
 
     handle->engine->idle();