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Audio/Video synchronization issue on multicast frame drops in DASH (Chrome browser)

Hello

I’ve got a source multicast stream that’s being transcoded by Wowza Streaming Engine Transcoder and packaged into DASH stream.

The source stream is configured like this:

{
  uri : "udp://239.239.6.16:1234",
  mpegtsMapTimeToSystemTime : "true",
  mpegtsLogIncompleteVideoFrames : "true"
}

The rest is configured as a standard Live HTTP Origin application.

After playing the transcoded DASH stream for more than 5 minutes in Chrome (regardless the player - Shaka, DASH-IF) I can see/hear an audio/video delay that grows over time. I think it can be related with UDP frame drops that happens occasionally with the source stream.

2017-11-21 16:41:07 WARN server comment - RTPDePacketizerMPEGTS[9/_definst_/9.stream]: RTPDePacketizerMPEGTS.flushVideoBuffer: Video frame incomplete, dropping[54527:0:false]: 12866545844070

Restarting the playback helps for a while but after another few mintues this problem comes back.

This WARNing happens ~50 times every 10 minutes, so with input stream FPS=25 the delay grows 2 seconds every 10 minutes.

It’s related only with Google Chrome browser as Firefox, VLC or other browsers/players seem to handle those drops.

I can provide more information if requested: transcoded stream or my application’s configuration.

Also, please make sure you read the issue that I created on GitHub’s page of Google Shaka Player: https://github.com/google/shaka-player/issues/1132 and the the one that Shaka Player developers referenced there: https://github.com/google/shaka-player/issues/707