--- a/content/media/webaudio/ConvolverNode.cpp
+++ b/content/media/webaudio/ConvolverNode.cpp
@@ -139,17 +139,17 @@ public:
     } else {
       if (aInput.mVolume != 1.0f) {
         // Pre-multiply the input's volume
         uint32_t numChannels = aInput.mChannelData.Length();
         AllocateAudioBlock(numChannels, &input);
         for (uint32_t i = 0; i < numChannels; ++i) {
           const float* src = static_cast<const float*>(aInput.mChannelData[i]);
           float* dest = static_cast<float*>(const_cast<void*>(input.mChannelData[i]));
-          AudioBlockAddChannelWithScale(src, aInput.mVolume, dest);
+          AudioBlockCopyChannelWithScale(src, aInput.mVolume, dest);
         }
       }
 
       if (mLeftOverData <= 0) {
         nsRefPtr<PlayingRefChanged> refchanged =
           new PlayingRefChanged(aStream, PlayingRefChanged::ADDREF);
         NS_DispatchToMainThread(refchanged);
       }