diff --git a/util/test/demos/test_common.cpp b/util/test/demos/test_common.cpp
index 81b6b39e5..04f55acb7 100644
--- a/util/test/demos/test_common.cpp
+++ b/util/test/demos/test_common.cpp
@@ -206,7 +206,7 @@ bool SpvCompilationSupported()
   if(!pipe)
     return false;
 
-  msleep(20);
+  msleep(250);
 
   int code = pclose(pipe);
 
diff --git a/util/test/demos/vk/vk_test.cpp b/util/test/demos/vk/vk_test.cpp
index ae899a462..0b23bf300 100644
--- a/util/test/demos/vk/vk_test.cpp
+++ b/util/test/demos/vk/vk_test.cpp
@@ -391,15 +391,17 @@ bool VulkanGraphicsTest::IsSupported()
     return true;
 
   static bool glslcChecked = false;
+  static bool glslcSupported = false;
 
   if(!glslcChecked)
   {
-    static bool glslcSupported = SpvCompilationSupported();
-
-    if(!glslcSupported)
-      return false;
+    glslcChecked = true;
+    glslcSupported = SpvCompilationSupported();
   }
 
+  if(!glslcSupported)
+    return false;
+
   return volkInitialize() == VK_SUCCESS;
 }