David, curious, do you subscribe to the channel and are you signed in when this happens?

Had the same issue. Wes Severson was looking into it and mentioned that the platform provider was going to be adding features. You might try putting your video on something like YouTube, G drive, Dropbox, etc and then posting a link to it.

Are you watching on your phone or computer, not that it should make a difference. I thought you had to "join" the chat or "subscribe" to the channel.

These are good exercises