diff --git a/media/base/multi_channel_resampler.cc b/media/base/multi_channel_resampler.cc
index 019bd8fa6df37..9fd0e15ade1bb 100644
--- a/media/base/multi_channel_resampler.cc
+++ b/media/base/multi_channel_resampler.cc
@@ -48,7 +48,14 @@ MultiChannelResampler::MultiChannelResampler(int channels,
 MultiChannelResampler::~MultiChannelResampler() = default;
 
 void MultiChannelResampler::Resample(int frames, AudioBus* audio_bus) {
-  DCHECK_EQ(static_cast<size_t>(audio_bus->channels()), resamplers_.size());
+  // SECURITY: When SnooperNode is configured with input_params and
+  // output_params that both use CHANNEL_LAYOUT_DISCRETE but have different
+  // channel counts, it picks ChannelMixStrategy::kNone and calls Resample()
+  // with an output_bus whose channel count exceeds resamplers_.size(). The
+  // extra channels are then left uninitialized and disclosed to the renderer
+  // via loopback shared memory. Upgrade the existing DCHECK to a CHECK so the
+  // mismatch becomes a safe crash instead of a cross-process heap leak.
+  CHECK_EQ(static_cast<size_t>(audio_bus->channels()), resamplers_.size());
 
   const size_t total_frames = base::checked_cast<size_t>(frames);
   // Optimize the single channel case to avoid the chunking process below.