diff --git a/miniwin/miniwin/src/include/miniwin_d3drm_p.h b/miniwin/miniwin/src/include/miniwin_d3drm_p.h
index 81f5d330..88b5bda0 100644
--- a/miniwin/miniwin/src/include/miniwin_d3drm_p.h
+++ b/miniwin/miniwin/src/include/miniwin_d3drm_p.h
@@ -29,9 +29,6 @@ class Direct3DRMArrayBase : public ArrayInterface {
 			return DDERR_INVALIDPARAMS;
 		}
 		auto inImpl = static_cast<ActualType*>(in);
-		if (!inImpl) {
-			return DDERR_INVALIDPARAMS;
-		}
 		inImpl->AddRef();
 		m_items.push_back(inImpl);
 		return DD_OK;
diff --git a/miniwin/miniwin/src/miniwin_d3drmframe.cpp b/miniwin/miniwin/src/miniwin_d3drmframe.cpp
index 0e849969..4c6c738e 100644
--- a/miniwin/miniwin/src/miniwin_d3drmframe.cpp
+++ b/miniwin/miniwin/src/miniwin_d3drmframe.cpp
@@ -46,10 +46,10 @@ HRESULT Direct3DRMFrameImpl::QueryInterface(const GUID& riid, void** ppvObject)
 
 HRESULT Direct3DRMFrameImpl::AddChild(IDirect3DRMFrame* child)
 {
-	Direct3DRMFrameImpl* childImpl = static_cast<Direct3DRMFrameImpl*>(child);
-	if (!childImpl) {
+	if (!child) {
 		return DDERR_GENERIC;
 	}
+	Direct3DRMFrameImpl* childImpl = static_cast<Direct3DRMFrameImpl*>(child);
 	if (childImpl->m_parent) {
 		if (childImpl->m_parent == this) {
 			return DD_OK;
@@ -198,8 +198,7 @@ HRESULT Direct3DRMFrameImpl::SetColor(D3DCOLOR c)
 
 HRESULT Direct3DRMFrameImpl::SetColorRGB(float r, float g, float b)
 {
-	SetColor(r, g, b, 1.f);
-	return DD_OK;
+	return SetColor(r, g, b, 1.f);
 }
 
 HRESULT Direct3DRMFrameImpl::SetMaterialMode(D3DRMMATERIALMODE mode)