--- a/dom/media/AudioSegment.h
+++ b/dom/media/AudioSegment.h
@@ -182,17 +182,19 @@ struct AudioChunk {
         if (aOther.mChannelData[channel] != AddAudioSampleOffset(mChannelData[channel],
             mBufferFormat, int32_t(mDuration))) {
           return false;
         }
       }
     }
     return true;
   }
-  bool IsNull() const { return mBuffer == nullptr; }
+  bool IsNull() const {
+    return mBuffer == nullptr;
+  }
   void SetNull(StreamTime aDuration)
   {
     mBuffer = nullptr;
     mChannelData.Clear();
     mDuration = aDuration;
     mVolume = 1.0f;
     mBufferFormat = AUDIO_FORMAT_SILENCE;
     mPrincipalHandle = PRINCIPAL_HANDLE_NONE;
@@ -328,54 +330,63 @@ public:
       }
       mDuration += c.mDuration;
     }
   }
 
   void ResampleChunks(SpeexResamplerState* aResampler,
                       uint32_t aInRate,
                       uint32_t aOutRate);
-
   void AppendFrames(already_AddRefed<ThreadSharedObject> aBuffer,
                     const nsTArray<const float*>& aChannelData,
                     int32_t aDuration, const PrincipalHandle& aPrincipalHandle)
   {
     AudioChunk* chunk = AppendChunk(aDuration);
     chunk->mBuffer = aBuffer;
+
+    MOZ_ASSERT(chunk->mBuffer || aChannelData.IsEmpty(), "Appending invalid data ?");
+
     for (uint32_t channel = 0; channel < aChannelData.Length(); ++channel) {
       chunk->mChannelData.AppendElement(aChannelData[channel]);
     }
     chunk->mBufferFormat = AUDIO_FORMAT_FLOAT32;
 #ifdef MOZILLA_INTERNAL_API
     chunk->mTimeStamp = TimeStamp::Now();
 #endif
     chunk->mPrincipalHandle = aPrincipalHandle;
   }
   void AppendFrames(already_AddRefed<ThreadSharedObject> aBuffer,
                     const nsTArray<const int16_t*>& aChannelData,
                     int32_t aDuration, const PrincipalHandle& aPrincipalHandle)
   {
     AudioChunk* chunk = AppendChunk(aDuration);
     chunk->mBuffer = aBuffer;
+
+    MOZ_ASSERT(chunk->mBuffer || aChannelData.IsEmpty(), "Appending invalid data ?");
+
     for (uint32_t channel = 0; channel < aChannelData.Length(); ++channel) {
       chunk->mChannelData.AppendElement(aChannelData[channel]);
     }
     chunk->mBufferFormat = AUDIO_FORMAT_S16;
 #ifdef MOZILLA_INTERNAL_API
     chunk->mTimeStamp = TimeStamp::Now();
 #endif
     chunk->mPrincipalHandle = aPrincipalHandle;
+
   }
   // Consumes aChunk, and returns a pointer to the persistent copy of aChunk
   // in the segment.
   AudioChunk* AppendAndConsumeChunk(AudioChunk* aChunk)
   {
     AudioChunk* chunk = AppendChunk(aChunk->mDuration);
     chunk->mBuffer = aChunk->mBuffer.forget();
     chunk->mChannelData.SwapElements(aChunk->mChannelData);
+
+    MOZ_ASSERT(chunk->mBuffer || aChunk->mChannelData.IsEmpty(), "Appending invalid data ?");
+
     chunk->mVolume = aChunk->mVolume;
     chunk->mBufferFormat = aChunk->mBufferFormat;
 #ifdef MOZILLA_INTERNAL_API
     chunk->mTimeStamp = TimeStamp::Now();
 #endif
     chunk->mPrincipalHandle = aChunk->mPrincipalHandle;
     return chunk;
   }