Hi, yes it's films that are on the BT TV platform and not from any other app that is stored on the device.
same issue here on 2 Samsung Smart TV's that we've tried.
They are BT adverts, it's only recently started happening. We only noticed as of yesterday but may not have used the app for a week or more.
The adverts are the same as if you leave the app sitting at the menu (for channel selection, etc.) for 5 minutes, so it looks as if the App is not recognising that you are watching something instead of sitting idle at the menu.
The sound of whatever you are watching continues playing, you can use any of the navigation keys on the TV remote to get the picture back, if you press a key within the 5 minutes it will stop the adverts coming up for a further 5 minutes.
As it is, the app is pretty much unuseable/too frustrating to use.
Many thanks. I'll check out this evening. I appreciate you reacting and resolving.