diff --git a/cores/validation/validation_usb_host/build_as6/test.cppproj b/cores/validation/validation_usb_host/build_as6/test.cppproj
index 2effeff9bc50ff0e988a8f5969971baa206e7df7..44536e6b8c1a920a768d151fd170d39dc6be5a1b 100644
--- a/cores/validation/validation_usb_host/build_as6/test.cppproj
+++ b/cores/validation/validation_usb_host/build_as6/test.cppproj
@@ -345,14 +345,14 @@
       <SubType>compile</SubType>
       <Link>core\Stream.h</Link>
     </Compile>
-    <Compile Include="..\..\..\arduino\syscalls.c">
+    <None Include="..\..\..\arduino\syscalls.c">
       <SubType>compile</SubType>
       <Link>core\syscalls.c</Link>
-    </Compile>
-    <Compile Include="..\..\..\arduino\syscalls.h">
+    </None>
+    <None Include="..\..\..\arduino\syscalls.h">
       <SubType>compile</SubType>
       <Link>core\syscalls.h</Link>
-    </Compile>
+    </None>
     <Compile Include="..\..\..\arduino\Tone.h">
       <SubType>compile</SubType>
       <Link>core\Tone.h</Link>