--- a/dom/media/mediasource/MediaSourceReader.cpp
+++ b/dom/media/mediasource/MediaSourceReader.cpp
@@ -394,20 +394,22 @@ MediaSourceReader::ContinueShutdown()
     return;
   }
 
   mAudioTrack = nullptr;
   mAudioReader = nullptr;
   mVideoTrack = nullptr;
   mVideoReader = nullptr;
 
+#ifdef MOZ_FMP4
   if (mSharedDecoderManager) {
     mSharedDecoderManager->Shutdown();
     mSharedDecoderManager = nullptr;
   }
+#endif
 
   MOZ_ASSERT(mAudioPromise.IsEmpty());
   MOZ_ASSERT(mVideoPromise.IsEmpty());
 
   mAudioWaitPromise.RejectIfExists(WaitForDataRejectValue(MediaData::AUDIO_DATA, WaitForDataRejectValue::SHUTDOWN), __func__);
   mVideoWaitPromise.RejectIfExists(WaitForDataRejectValue(MediaData::VIDEO_DATA, WaitForDataRejectValue::SHUTDOWN), __func__);
 
   MediaDecoderReader::Shutdown()->ChainTo(mMediaSourceShutdownPromise.Steal(), __func__);