Wowza Community

nDVR hls play is buffering always during live as well as playback

I am using nDVR in my live application. It is buffering a lot with even high speed connection at the client. should I optimize anything ? Media Cache is already enabled. As per my observation it starts buffering exactly at 9 seconds or 10 seconds and then continues buffering at multiples of that number my streaming engine version Wowza Streaming Engine Version 4.8.0. This is causing bad experience to my viewers

Please help me in avoiding buffering, also latency is something between 60 to 120 seconds

I would first of all recommend upgrading your Engine version since we have made multiple fixes to Engine and MediaCache since 4.8.0. We are now on version 4.8.13. You can safely upgrade in a testing environment so you do not affect anything in production.

As far as the buffering, it’s possible your network can’t handle the amount of data you are trying to send. If the buffering is the fault of the video broadcaster, then you can take a look at the following:

  1. Reduce the bitrate.
  2. Make sure you’re not sending through too many (FPS) frames per second. Are you sending 30FPS as we suggest?
  3. Make sure your browser cache has been cleared and isn’t slowing down the transmission.
  4. Make sure your graphics cards are updated
  5. Poor wi-fi and insufficient bandwidth are two different things.

Lack of available bandwidth is often the cause of buffering.

It’s generally recommended that your bandwidth be twice your broadcast bitrate. If you plan to deliver a higher resolution stream at 4K, you may even want to consider two and a half times the bitrate to play it safe.

If the buffering is happening to viewers due to poor network quality on their end, are you utilizing Adaptive Bitrate Streaming?

The best way for us accurately diagnose is through a support ticket though, that HLS latency is not within a normal range. We’d need to review your configuration for MediaCache, nDVR and HLS playback as well as investigate your encoder settings.

We’ll help you get it within normal latency range and reduce the buffering, it will just require a closer look. That amount of buffering is a very poor viewer experience as you noted and I suggest you submit a ticket right away so we can correct it. Thanks.