diff --git a/osx/cmAudioPortOsx.c b/osx/cmAudioPortOsx.c
index 311c1dc..9d428c9 100644
--- a/osx/cmAudioPortOsx.c
+++ b/osx/cmAudioPortOsx.c
@@ -504,7 +504,7 @@ OSStatus _cmApOsxSystemDeviceIOProc(	AudioDeviceID			inDevice,
 }
 
 
-cmApRC_t      cmApOsxInitialize( cmRpt_t* rpt )
+cmApRC_t      cmApOsxInitialize( cmRpt_t* rpt, unsigned baseApDevIdx )
 {
   cmApRC_t       rc            = kOkApRC;
   Boolean        outWritableFl = false;
diff --git a/osx/cmAudioPortOsx.h b/osx/cmAudioPortOsx.h
index 3b25922..f7e4649 100644
--- a/osx/cmAudioPortOsx.h
+++ b/osx/cmAudioPortOsx.h
@@ -5,7 +5,7 @@
 extern "C" {
 #endif
 
-  cmApRC_t      cmApOsxInitialize( cmRpt_t* rpt );
+  cmApRC_t      cmApOsxInitialize( cmRpt_t* rpt, unsigned baseApDevIdx );
   cmApRC_t      cmApOsxFinalize();
   cmApRC_t      cmApOsxDeviceCount();
   const char*   cmApOsxDeviceLabel(          unsigned devIdx );