Videos stopped working

So I have a published app with videos in it. Each video is an HLS stream. They all stopped working recently in the Android app (although they stream elsewhere). The stream doesn’t appear to have changed, and the app hasn’t been updated, so I’m wondering if it is an Android update to webview or something like that.
In experiments this evening it looks like I can use a Vimeo link to good effect instead, which is I think what I will now do. Anyway, thought I’d mention.