diff --git a/src/apps/soundrecorder/ScopeView.cpp b/src/apps/soundrecorder/ScopeView.cpp
index de43deb1c8..4a847e0635 100644
--- a/src/apps/soundrecorder/ScopeView.cpp
+++ b/src/apps/soundrecorder/ScopeView.cpp
@@ -258,7 +258,7 @@ ScopeView::SetRightTime(bigtime_t timestamp)
 
 
 void
-ScopeView::RenderTrack(BMediaTrack *track, media_format &format)
+ScopeView::RenderTrack(BMediaTrack *track, const media_format &format)
 {
 	fMediaTrack = track;
 	fPlayFormat = format;
diff --git a/src/apps/soundrecorder/ScopeView.h b/src/apps/soundrecorder/ScopeView.h
index db5f09aa83..fd76bde7a9 100644
--- a/src/apps/soundrecorder/ScopeView.h
+++ b/src/apps/soundrecorder/ScopeView.h
@@ -25,7 +25,7 @@ public:
 	void SetLeftTime(bigtime_t timestamp);
 	void SetRightTime(bigtime_t timestamp);
 	void SetTotalTime(bigtime_t timestamp, bool reset);
-	void RenderTrack(BMediaTrack *track, media_format &format);
+	void RenderTrack(BMediaTrack *track, const media_format &format);
 	void CancelRendering();
 	virtual void FrameResized(float width, float height);
 	virtual void MouseDown(BPoint position);