Is It Possible to Autoplay VMAP Midroll Ads Without Muting on iOS Safari with HLS?

[311390J]

Have you read the Tutorials?
Yes

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

If the question is related to FairPlay, have you read the tutorial?
N/A

What version of Shaka Player are you using?
4.16.9

What browser and OS are you using?
iOS 26.1 / Safari

Please ask your question
When using interstitial_ad_manager.js to insert midroll ads via VMAP, is it possible for ads to autoplay unmuted on iOS Safari when using HLS?

I am using the following VMAP:

<vmap:VMAP xmlns:vmap="http://www.iab.net/vmap-1.0" version="1.0">
    <vmap:AdBreak timeOffset="00:00:30.000" breakType="linear" breakId="midroll-foo">
        <vmap:AdSource allowMultipleAds="true" followRedirects="true">
            <vmap:AdTagURI templateType="vast4">
                <![CDATA[ https://ad_server_url.com/ad?foo=1 ]]>
            </vmap:AdTagURI>
        </vmap:AdSource>
    </vmap:AdBreak>
</vmap:VMAP>

The player is configured as follows (using a custom UI):

const adManager = shaka.getAdManager();
adManager.initInterstitial(adContainer, shaka, video);
await adManager.addAdUrlInterstitial(vmap);

Autoplay is disabled on the viewing page.

Under these conditions, when playback starts and runs until 0:30, the ad-started event fires, but the ad remains paused. Based on the following tests, I believe this is due to iOS autoplay policies:

• If the user taps the screen shortly before the ad break, the ad will autoplay.
  • https://developer.mozilla.org/en-US/docs/Web/Media/Guides/Autoplay#autoplay_availability
  • https://webkit.org/blog/6784/new-video-policies-for-ios/
• If I set the ad video element’s muted property to true when the ad-started event fires, the ad will autoplay.
  • https://developer.apple.com/documentation/webkit/delivering-video-content-for-safari#Play-a-Video-in-Your-Webpage
• Preroll ads (AdBreak timeOffset="start") autoplay immediately after the user initiates playback.

[avelad]

are you using MSE or src= for load the primary content?

[311390J]

are you using MSE or src= for load the primary content?

We are using the src attribute to load the primary content.

[avelad]

Okay, I'll try it on Thursday, I'll give you feedback on whether we can do something. Thanks for your patience!

[avelad]

Try to change ads.supportsMultipleMediaElements = false (config) and try again.

[311390J]

Thank you for your reply.

Setting ads.supportsMultipleMediaElements = false resolved the issue where video playback would stop during ad playback.

The transition from the primary content to the ad is now smooth, but after the ad ends, the primary content does not resume. Specifically, video.currentTime becomes NaN after the ad finishes. However, this might be an issue with my application.

If I have any further updates, I will contact you again.

[311390J]

I am currently playing the content with streaming.preferNativeHls = true.
In this case, after switching from the primary content to the ad, playback stalls when it should return from the ad to the primary content.

As I mentioned in my previous post, video.currentTime becomes NaN at that point.

I have also confirmed that this issue does not occur when streaming.preferNativeHls = false.

If you have any suggestions or if there is anything else I could try, I would greatly appreciate your advice. Thank you very much for your support.

[311390J]

This may be a separate issue from my previous post, but I have observed some unexpected behavior and would like to report it.

When I set ads.supportsMultipleMediaElements = false, meaning only one video element is used, and play ads using the following VMAP, both the mid-roll ad at 0:30.430 and the post-roll ad are played together at the mid-roll position.
I have confirmed this behavior not only on iOS/Safari, but also on Windows 11/Chrome.

<vmap:VMAP xmlns:vmap="http://www.iab.net/vmap-1.0" version="1.0">
  <vmap:AdBreak timeOffset="00:00:30.430" breakType="linear" breakId="midroll">
    <vmap:AdSource allowMultipleAds="true" followRedirects="true">
      <vmap:AdTagURI templateType="vast4">
        <![CDATA[ https://ad_server_url.com/ad?sec=30 ]]>
      </vmap:AdTagURI>
    </vmap:AdSource>
  </vmap:AdBreak>
  <vmap:AdBreak timeOffset="end" breakType="linear" breakId="postroll">
    <vmap:AdSource allowMultipleAds="true" followRedirects="true">
      <vmap:AdTagURI templateType="vast4">
        <![CDATA[ https://ad_server_url.com/ad?sec=30 ]]>
      </vmap:AdTagURI>
    </vmap:AdSource>
  </vmap:AdBreak>
</vmap:VMAP>

The content structure is as follows:

primary content: |--30sec--|         |--30sec--|
ad             : |         |--30sec--|         |--30sec--|

After the mid-roll ad finishes, I expected the primary content to resume, but instead, playback occurred as follows:

primary content: |--30sec--|                   |--30sec--|
ad             : |         |--30sec--|--30sec--|

As far as I can tell, this issue has been present since version 4.16.1. I have not checked earlier versions.

[avelad]

Can you test with the main branch?

[311390J]

I have tested with the main branch.

As a result, with supportsMultipleMediaElements = false and without performing any seek operations,
I was able to play both the primary content and ads without any stalling by reloading the manifest after the ad finished.

Here are the details:

• supportsMultipleMediaElements = true (using adContainer)
  • The behavior is the same as previously reported: playback stops at the ad break.
• supportsMultipleMediaElements = false (not using adContainer)
  • The ad plays automatically, but after the ad finishes, video.currentTime becomes NaN and playback stalls.
    • In this state, if I reload the manifest, playback can resume from where it left off.
  • If I do not perform any seek operations and reload the manifest as described above, both the primary content and ads can be played without issues.
  • If I perform a seek operation, one of the following issues may occur:
    • For example, if there is a 1:00 primary content with a 15-second ad at 0:30 and another 15-second ad at 1:00 (AdBreak: timeOffset="end"), and I seek to around 0:55 during playback:
      1. There are cases where the post-roll ad is played immediately after the mid-roll ad.
         • If I seek to around 0:55 right after starting playback, the mid-roll ad at 0:30 is played, and immediately after, the post-roll ad is also played.
         • When this occurs, even if playback continues to 1:00 after the ads, the post-roll ad is not played again.
      2. After the mid-roll ad is played and the main content resumes, switching to the post-roll ad may result in a shaka error 7000.

If there are any other conditions I should test, I would appreciate your guidance.