Embedded PPT videos lagging/choppy in Webinar

[LB_OCE]

I have a panelist presenting ongoing Webinars with us. When we reviewed her slides -- which included embedded videos -- with just the two of us in a Meeting, the audio/video synced up no problem. When we presented the actual Webinar on the day of, the audio played smoothly but the video was choppy and lagging. These were embedded video files, not embedded YouTube links.

We are running a Webinar (I am Host, she is Panelist with co-host permission) and she is using a Mac (unsure which iOS). She's doing Advanced --> Share Portion of Screen (so she can still see her PPT Presenter View), and checking both Optimize Sound and Optimize for Video Sharing. We are recording the Webinar for asynchronous viewing. We have made sure both her Zoom and her PPT are fully updated. She is spot lit and keeps her camera on; my camera is off.

Please help!

[Ray_Harwood]

Welcome to the Zoom Community, @LB_OCE.

There are several potential issues to look out for:

Don't Share "Portion of Screen"

This is almost always a no-no, creating pixelation downstream.  I see some folks using the Presenters view, and just sharing the upper left portion of their screen where the "live" slide is shown:

This area is about 1250 x 710 by default.  When expanded to a full screen view on your attendee displays at 1920x1280, you're getting about 60% pixel expansion across the screen, causing all sorts of issues, including color distortion and "blockiness" pixelation.

I always work with my presenters in advance and require that they present full-screen using this method, or allowing me to present for them, while they "follow along" on their Presenter View or printed notes.  I use a software tool called SlidesClicker to facilitate this and eliminate the need to say "Next slide, please" every time.  See my presenter guide for SlidesClicker here.  If you're going to be doing a lot of webinar production, this tool will help you immensely.

Embedded Video vs Linked Video

My experience is that embedded videos in PowerPoints "play nicer", since the video is right there in the PPT file and generally cast to the screen without delay.  If you are linked to a file or URL -- whether locally on the presenter's computer or "out there on the web somewhere" -- there's a delay which often varies considerably based on time of day and changes in your network location.

Testing

Sounds like you did some testing, but just as some advice: Test in as real of a situation as you can create. Same time of day and hopefully same day of the week, same network, same computer, other hosts/co-hosts that would present on the same network, etc.  Also be sure to test your recording.  If you are going to live-stream, make a test live-stream and watch the recorded version to view the results.  If you are going to record it through Zoom, I always recommend Zoom Cloud recording as opposed to Local Recording, and turn on as many of the various recording settings as you can:

• Green items should be enabled
• Red items should not be enabled.
• Unmarked items don't matter to video quality.
• Orange items:
  • Most people don't have live spoken interpretation done.
  • If you have Zoom Events and are using Production Studio, you definitely want to record the Production Studio-produced video!
  • I don't like having the speakers names on-screen when editing - I can add them in during the editing process so they're legible and look nicer.

Summary

You've got the right idea with testing, asking questions, and being willing to learn more.  I've been producing Zoom Events, Webinars, and Meetings for clients since the start of the pandemic, and it took me a long time to learn about these details.  I'm always happy to share what I know with people like you!

[LB_OCE]

Hi Ray,

Thanks for your thoughtful reply. A few comments/thoughts based on your post:

• What's the best way to share a slideshow in Presenter View without having the notes visible, if not using Portion of Screen? Having me share and forward through the slides is not feasible given our setup; it must be done by the presenter. 
• We have the video embedded in the PPT (it is not a YouTube link).
• We are unable to test in Webinar format, due to the constraints of our Webinar license / the number of programs we run weekly. We meet with presenters ahead of time in a Meeting, and then we run the programs as Webinars.
• Other details: We always record programs, and they are always recorded to the cloud. We never do livestream programs, Production Studio things, nor interpretation programs outside of auto-generated closed captions as triggered by the participants.

We run about 4-5 Webinars a week, and I've never experienced issues with videos becoming laggy in slideshows. I've triaged to the best of my ability but still keep running into this problem so I'm not sure what's going on here, which is what brought me to this forum. And unfortunately, since Zoom doesn't let us view other people's settings via screenshare, when trying to assist remotely I can only guesstimate what our presenter is seeing on their end.

Most of our presenters are very adept at troubleshooting these issues themselves / have dual monitors for Presenter View / are able to have separate tabs open to play videos. Some of our presenters, however, need more guidance to the technological aspects; this, with the lagging videos in screensharing, is one such instance.

Any other thoughts on how to eliminate lagging videos (but audio going in real-time) embedded in PPT slideshows in Webinars?

Thanks!