--- a/dom/media/webrtc/MediaEngineDefault.cpp
+++ b/dom/media/webrtc/MediaEngineDefault.cpp
@@ -87,17 +87,16 @@ MediaEngineDefaultVideoSource::Allocate(
   FlattenedConstraints c(aConstraints);
 
   // Mock failure for automated tests.
   if (c.mDeviceId.mIdeal.find(NS_LITERAL_STRING("bad device")) !=
       c.mDeviceId.mIdeal.end()) {
     return NS_ERROR_FAILURE;
   }
 
-
   // emulator debug is very, very slow; reduce load on it with smaller/slower fake video
   mOpts = aPrefs;
   mOpts.mWidth = c.mWidth.Get(aPrefs.mWidth ? aPrefs.mWidth :
 #ifdef DEBUG
                               MediaEnginePrefs::DEFAULT_43_VIDEO_WIDTH/2
 #else
                               MediaEnginePrefs::DEFAULT_43_VIDEO_WIDTH
 #endif
@@ -481,18 +480,16 @@ MediaEngineDefaultAudioSource::Start(con
   MOZ_ASSERT(mStream, "SetTrack() must happen before Start()");
   MOZ_ASSERT(IsTrackIDExplicit(mTrackID), "SetTrack() must happen before Start()");
 
   if (!mSineGenerator) {
     // generate sine wave (default 1KHz)
     mSineGenerator = new SineWaveGenerator(mStream->GraphRate(), mFreq);
   }
 
-  mLastNotify = 0;
-
   MutexAutoLock lock(mMutex);
   mState = kStarted;
   return NS_OK;
 }
 
 nsresult
 MediaEngineDefaultAudioSource::Stop(const RefPtr<const AllocationHandle>& aHandle)
 {

--- a/dom/media/webrtc/MediaEngineDefault.h
+++ b/dom/media/webrtc/MediaEngineDefault.h
@@ -168,17 +168,17 @@ protected:
   Mutex mMutex;
 
   // Current state of this source.
   // Set under mMutex on the owning thread. Accessed under one of the two.
   MediaEngineSourceState mState = kReleased;
   RefPtr<SourceMediaStream> mStream;
   TrackID mTrackID = TRACK_NONE;
 
-  // Accessed in ::Start(), then on Pull (from MSG thread)
+  // Accessed in Pull (from MSG thread)
   TrackTicks mLastNotify = 0;
   uint32_t mFreq = 1000; // ditto
 
   // Created on Start, then accessed from Pull (MSG thread)
   nsAutoPtr<SineWaveGenerator> mSineGenerator;
 };