diff --git a/reactos/drivers/wdm/audio/backpln/portcls/pin_wavecyclic.cpp b/reactos/drivers/wdm/audio/backpln/portcls/pin_wavecyclic.cpp
index 0520480ae92..4da90868a70 100644
--- a/reactos/drivers/wdm/audio/backpln/portcls/pin_wavecyclic.cpp
+++ b/reactos/drivers/wdm/audio/backpln/portcls/pin_wavecyclic.cpp
@@ -1222,6 +1222,10 @@ CPortPinWaveCyclic::Init(
     // delay of 10 milisec
     m_Delay = Int32x32To64(10, -10000);
 
+    // sanity checks
+    PC_ASSERT(m_CommonBufferSize);
+    PC_ASSERT(m_CommonBuffer);
+
     Status = m_Stream->SetNotificationFreq(10, &m_FrameSize);
     PC_ASSERT(NT_SUCCESS(Status));
     PC_ASSERT(m_FrameSize);