Embedded video sometimes plays as it buffers, other times it must load completely

May 16, 2016

Hi Heroes,

Here is the setup... We have a course with two slides, each with an embedded video:

Slide1 4 minutes (20MB mp4)

Slide 2 8 minutes (40MB mp4)

The videos set to play on-click. I have heavily compressed them to the point they are looking rather grainy. And I have used qt-faststart. The course is hosted on an external LMS. 

I encounter a buffering problem when jumping between the two slides. If I play Slide1 first, the video plays fine (you see via the seekbar the video is buffering). While Slide1 is playing, I click on Slide2, the video in Slide1 stops, but you continue to see the Slide1 video is buffering, and you get the spinning "buffering" icon. After 30 seconds or so, Slide2 opens. You can see that via the seekbar that the entire video2 has been buffered and the video plays fine.

This behavior is the same if you play Slide2 and then Slide1; the issue isn't with the video files. The first video that is played in this scenario (Slide 1 or 2) always plays while it is being buffered. The issue is when you try to play a second video.

My question is, is there a way to get the first video to stop buffering and immediately jump to the second video and begin playing while it buffers - instead of having to wait for it to completely buffer? 




14 Replies
Ashley Terwilliger-Pollard

Hi Chris,

I may not be understanding how you're seeing the slide buffering from the seekbar, unless you mean something outside of the Storyline seekbar. Storyline is going to preload content as detailed here, and Storyline is set to progressively stream content as detailed here. In some cases, you may have an MP4 file that isn't properly formatted. As a result, learners may experience a long delay while the entire video downloads. If you have an MP4 file that's exhibiting this behavior, you may be able to correct it by using the method described here.

Chris Jones

Hi Ashley,

Thank you for the reply. I have looked at all the references you provided and I also had tried using the qt-faststart.exe to fix the videos - note qt didn't find anything to fix.

I apologize for not being very clear. I would post a screencast, but I don't have permission to post the videos externally. So I'll try explaining again.

 It seems there is something going on with the SL player. Once a video starts loading, clicking on another slide with a video causes the player to completely download the second video before it will play it. I am hoping someone has recommendations to prevent this issue.

I'll try to explain the scenario more clearly... the SL file has two videos, each on a slide, S1 and S2. I launch the course from our external LMS and do the follow actions: 

1) via the menu click S1. The video begins to play.
The seekbar has a light gray bar that indicates the video is loading in the background. The references you provided indicate this is what should happen. It's all good.

2) Before the S1 video is done loading, click the S2 slide
S2 doesn't open right away. Instead the S1 video stops, but you see via the seekbar that it continues to load in the background. Once it is loaded, there is an additional 30+ second delay. 

3) Finally S2 opens and the video plays. And via the seekbar you can see the S2 video has completely downloaded.

In the above scenario you can switch which video you open first; start with S2 and then click S1, S2 plays fine, but there is a delay before S1 plays. 


Ashley Terwilliger-Pollard

Hi Chris,

Thanks for that explanation. I'm still not sure I'm clear on where you're seeing the seekbar continue to load or buffer, I assume you mean the video seekbar not the slide timeline seekbar that is a part of the player?  I know you mentioned not being able to share here in the forums, but perhaps you could share an example .story file or a link to the course with us privately? If so you can send it to me here. 

If not, some other things I'd look at testing out:

  • Does this happen with every set of videos you have? What if you space it out with a slide inbetween (you could set that slide to automatically jump to slide 3 upon timeline start)? 
  • Have you tested this outside your LMS? You could use a site such as SCORM Cloud which is an free industry standard for LMS content, or look at republishing the course for web and upload to a testing site such as Tempshare.  
  • You mentioned the videos load fine on their own - where are you hosting/testing those videos? Are they locally or linked to another web site? Have you tried inserting them as web objects vs. embedding them into the course?
  • Are you able to try accessing the course using another internet connection? Perhaps hard wired vs. wifi or a coffee shop/home wifi vs. work? 
  • Are you seeing the same behavior across all browsers? 

Let me know if you are able to narrow things down a bit further with those ideas or if you'd like to share information using the link I included above. 

Stian Larsen

Old thread, but I've got the exact same problem.

Did you figure something out?

The description above explains exactly what I experience here:
-First video loads progressively, as it should, and therefor starts playing right away (while the rest is buffering). But upon switching to another video (slide or lightbox with a new video), the whole course hangs for about 30 seconds, while completely downloading the next video before starting the playback. The cursor and everything freezes inside the course for this duration.

Richard Hill

Hi Stian,  this is just a work around(not a fix) just in case you are really in a bind.  You can create an index file in a folder along with your video and  then bring it in as a webObject.  It seems to bypass the RAM SL needs.   The code you will need on your index can be found here: http://www.w3schools.com/html/html5_video.asp

note: this video player is simply that, and cannot trigger anything upon complete, but it doesn't lock up SL    : )

Ashley Terwilliger-Pollard

Hi Stian,

We did some extensive testing on Chris's file - and here was my final response to him from the case:

Thanks for your patience. I talked this over with my team and they confirmed the delay after clicking the next button to load another slide that is media intensive is expected and the length of that delay depends on the overall amount of media, the hosting location and where you're accessing it from in terms of download speed.

Also, they were curious if you've been able to test uploading it yourself to SCORM Cloud to confirm that you're not running into any other issues with publishing on your end or that it's more associated with the hosting solution and your LMS. As for testing at SCORM Cloud, I was recommending that as an alternative since the version of the course I published and upload there behave differently than the version you were hosting within your internal LMS. It would be a good way to also confirm that nothing else erratic has occurred during your publish set up that would account for a longer delay as opposed to what you saw in my version. Since some delay is by design as previously described, this would only help you ensure that you're LMS or internet connection are not also playing a role in any further lag time. 

With that in mind, it may be similar to what you're experiencing but we're always happy to help test it out. You can share your files with our Support Engineers by sending along here if you'd like. 

Stian Larsen

You say the delay is expected? I know that answer was for Chris problem, but he said it would hang for 30 second (while downloading the complete video) before starting to play. That can't be the expected behavior? :)

In my example, it's random whether or not it opens the video right away and starts buffering (I can see the gray bar buffering the video in the included video controls), or if it freezes for 30-40 seconds while downloading the whole movie (as can be seen in F12 diagnostics of the browser window or in the seek-bar of the video control when the video starts playing, as now the whole bar is gray and buffered).

The hosting location could not be the problem either, so I think this is either still some fault with my .mp4 videos and streaming (how do I export from Adobe Media Encoder CC to allow for smooth buffering/streaming?) or the way Articulate Storyline handles the buffering of videos. 

I tried the mp4 fix posted in support, but it did ask for .mov files, nto mp4. So nothing to do :)

Thanks for your help!

Ashley Terwilliger-Pollard

Hi Stian,

Well in Chris's case it was, based on the amount of media resources on his slide. Our team didn't experience as dramatic a delay, but it was still something we saw a bit of, so the delay can also be associated with the broadband/wifi available.

If you'd like us to test yours, we'd be happy too. Please reach out to our Support team here and upload the file. 

Stian Larsen

Ok, I understand :) Then my case is probably a bit different. I've got 4 videos, totalling about 600mb, on separate slides.

I 'm currently trying the quick-fix by using a index.html and linking it up as webobject instead of video, to see if that sorts it out. This is not optimal for a permanent solution though.

Some delay is to be expected anywhere, but more than a couple of seconds is not good, as users think the computer is frozen.

Internetspeed is not the issue in my case. Sometimes I can se the video is buffering, and it starts right away. Other times the course freezes for 30sek to 1 minute, before the video shows and starts playing.

Thanks for your comments so far. I will do some more debugging.

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