--- a/dom/media/mediasink/AudioSink.cpp
+++ b/dom/media/mediasink/AudioSink.cpp
@@ -337,17 +337,18 @@ uint32_t AudioSink::SampleToFrame(uint32
   return aSamples / mOutputChannels;
 }
 
 void AudioSink::NotifyAudioNeeded() {
   MOZ_ASSERT(mOwnerThread->IsCurrentThreadIn(),
              "Not called from the owner's thread");
 
   while (mAudioQueue.GetSize() &&
-         AudioQueuedInRingBufferMS() < mProcessedQueueThresholdMS) {
+         AudioQueuedInRingBufferMS() <
+             static_cast<uint32_t>(mProcessedQueueThresholdMS)) {
     // Check if there's room in our ring buffer.
     if (mAudioQueue.PeekFront()->Frames() >
         SampleToFrame(mProcessedSPSCQueue->AvailableWrite())) {
       SINK_LOG_V("Can't push %u frames. In ringbuffer %u / %u\n",
                  mAudioQueue.PeekFront()->Frames(),
                  SampleToFrame(mProcessedSPSCQueue->AvailableRead()),
                  SampleToFrame(mProcessedSPSCQueue->Capacity()));
       return;