HLS starts at 10s

[mseeley]

Have you read the FAQ and checked for duplicate open issues?
Yes

What version of Shaka Player are you using?

• Shaka: 2.4.6, 2.4.5, and 2.3.3.
• Our custom app combines Shaka v2.3.3 + mux.js v5.0.1. We are trying to update to Shaka >= v2.4.6 + mux.js v5.0.1.

Can you reproduce the issue with our latest release version?
Yes

Can you reproduce the issue with the latest code from master?
No, I honestly have not tried.

Are you using the demo app or your own custom app?
Demo and custom app.

If custom app, can you reproduce the issue using our demo app?
Yes

What browser and OS are you using?
Chrome 72, macOS 10.14.1

For embedded devices (smart TVs, etc.), what model and firmware version are you using?
n/a

What are the manifest and license server URIs?

• https://provider-media.plex.tv/22fedd71260e2e27c7025a751f800d97/video.m3u8
• Manifest and segments can be downloaded separately for local testing

What did you do?

• Load the 2.4.6 demo directly to the manifest above
  • Maximum small gap size: should be default 0.5
  • Jump large gaps is unchecked

What did you expect to happen?

Playback should begin at 0s. In our app, v2.3.3 + mux.js v5.0.1 play the stream from start time 0 without manifest.defaultPresentationDelay nor manifest.hls.defaultTimeOffset values. I believe there is a behavior change between 2.3.3 and 2.4.5 that I haven't been able to identify.

What actually happened?

• Stream jumps forwards to ~10s.
• Log displays Jumping forward 0.1154080000000004 seconds because of gap starting at 11.862333 and ending at 11.947666

Our upgrade to 2.4.5 and 2.4.6 both demonstrate that stream playback now starts at ~10s. The delay smells like a pre-roll presentation delay of some sort. It did not occur in 2.3.3.

These issues describe a 10s skip at start: #1625, #1011. The combined configuration workaround (shown below) doesn't change behavior.

this._shaka.configure({
  manifest: {
    // #1625
    defaultPresentationDelay: 0,
    hls: {
      // #1011
      defaultTimeOffset: 0
    }
  },
  streaming: {
    bufferingGoal: this.props.bufferingGoal,
    jumpLargeGaps: true,
    retryParameters: {
      maxAttempts: Infinity
    }
  },
  abr: {
    defaultBandwidthEstimate: this.props.defaultBandwidthEstimate
  }
});

[vaage]

@mseeley Most HLS content starts at 10 seconds, this is something that Apple's HLS packager does and so a lot of content starts at 10 seconds.

Is the player:

• skipping the first 10 seconds of your content

or is the player:

• saying your contents at timer=10 seconds and no actual content was skipped

[mseeley]

HI @vaage good question. I've just confirmed; the player is skipping the first 10s of content.

[mseeley]

@vaage, #1625 mentions a fix in 2.50 beta. I can confirm this is fixed in the 2.5.0-beta2 npm package without any of the configuration mentioned above. Diff: https://gist.github.com/mseeley/908f51ac71e33d08797857d742b34296.

[vaage]

@joeyparrish was #1602 cherry-picked into 2.4 (I don't see it in the changelog)? If not, is there any way to flag it to be cherry-picked in the future?

[joeyparrish]

It was not, but I just pushed it to v2.4.x in cd9d066, which will be released in v2.4.7. Sorry for the inconvenience! I didn't realize we had missed that fix.

[mseeley]

Thank you @vaage and @joeyparrish! Zero worries here. 😄

[mseeley]

Hi @joeyparrish 👋. I've been sleuthing in this repo to find a general 2.4.7 release plan/timing although I haven't found information. Will you please share some general thoughts on 2.4.7? No pushy request to release, just a request for a bit of context I can use to update state on our internal issue tracker. Thanks!

[joeyparrish]

Hi, @mseeley. I'm working on it today. We're a bit behind on everything, which is hard to tell since I haven't published a timeline or roadmap yet. That's coming soon, too, though.

[joeyparrish]

Just noticed that this is still in "needs triage". I'm going to go ahead and close as a duplicate of #1602 based on the history so far. The fix for that is in master (so you can try it out any time) and will be rolled into v2.4.7 very soon. Thanks!

[joeyparrish]

Fix released in v2.4.7.