diff --git a/media/webrtc/trunk/webrtc/modules/video_coding/rtt_filter.cc b/media/webrtc/trunk/webrtc/modules/video_coding/rtt_filter.cc
index 742f70f1c10a..b89832e3c1cb 100644
--- a/media/webrtc/trunk/webrtc/modules/video_coding/rtt_filter.cc
+++ b/media/webrtc/trunk/webrtc/modules/video_coding/rtt_filter.cc
@@ -49,8 +49,8 @@ void VCMRttFilter::Reset() {
   _filtFactCount = 1;
   _jumpCount = 0;
   _driftCount = 0;
-  memset(_jumpBuf, 0, kMaxDriftJumpCount);
-  memset(_driftBuf, 0, kMaxDriftJumpCount);
+  memset(_jumpBuf, 0, sizeof(_jumpBuf));
+  memset(_driftBuf, 0, sizeof(_driftBuf));
 }
 
 void VCMRttFilter::Update(int64_t rttMs) {