diff --git a/src/juce_appframework/audio/dsp/juce_AudioSampleBuffer.cpp b/src/juce_appframework/audio/dsp/juce_AudioSampleBuffer.cpp
index 257d3f5a74..8755982a83 100644
--- a/src/juce_appframework/audio/dsp/juce_AudioSampleBuffer.cpp
+++ b/src/juce_appframework/audio/dsp/juce_AudioSampleBuffer.cpp
@@ -145,7 +145,7 @@ void AudioSampleBuffer::setSize (const int newNumChannels,
                                  const bool clearExtraSpace,
                                  const bool avoidReallocating) throw()
 {
-    jassert (numChannels > 0 && numChannels <= maxNumAudioSampleBufferChannels);
+    jassert (newNumChannels > 0 && newNumChannels <= maxNumAudioSampleBufferChannels);
 
     if (newNumSamples != size || newNumChannels != numChannels)
     {