diff --git a/reactos/drivers/wdm/audio/backpln/portcls/guids.cpp b/reactos/drivers/wdm/audio/backpln/portcls/guids.cpp
index 457868d2c62..4496e5785e1 100644
--- a/reactos/drivers/wdm/audio/backpln/portcls/guids.cpp
+++ b/reactos/drivers/wdm/audio/backpln/portcls/guids.cpp
@@ -57,7 +57,7 @@ const GUID IID_IDmaChannel = {0x22C6AC61L, 0x851B, 0x11D0, {0x9A, 0x7F, 0x00, 0x
 const GUID IID_IRegistryKey = {0xE8DA4302l, 0xF304, 0x11D0, {0x95, 0x8B, 0x00, 0xC0, 0x4F, 0xB9, 0x25, 0xD3}};
 const GUID IID_IServiceSink = {0x22C6AC64L, 0x851B, 0x11D0, {0x9A, 0x7F, 0x00, 0xAA, 0x00, 0x38, 0xAC, 0xFE}};
 const GUID IID_IPortClsVersion = {0x7D89A7BBL, 0x869B, 0x4567, {0x8D, 0xBE, 0x1E, 0x16, 0x8C, 0xC8, 0x53, 0xDE}};
-const GUID IID_IUnknown = {0x00000000, 0x0000, 0x0000, {0x00, 0x00, 0xC0, 0x00, 0x00, 0x00, 0x00, 0x46}};
+const GUID IID_IUnknown = {0x00000000, 0x0000, 0x0000, {0xC0, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x46}};
 const GUID IID_IPortEvents = {0xA80F29C4L, 0x5498, 0x11D2, {0x95, 0xD9, 0x00, 0xC0, 0x4F, 0xB9, 0x25, 0xD3}};
 
 const GUID KSNAME_PIN           = {0x146F1A80, 0x4791, 0x11D0, {0xA5, 0xD6, 0x28, 0xDB, 0x04, 0xC1, 0x00, 0x00}};