I've been having an issue lately where random channels won't play. I will get a Playback Failed message. I originally thought I would have to rescan, however the channels play at the server. Only after force stopping the app will this clear up. Also, let's say for example, TBS gets the error and I force stop and restart. TBS will play but another channel like SyFy or something else won't. Again, a force stop and restart fixes it.
This only seems to be the case at the client level as I would check at my server when the probem occurs. Everytime, the channels in question worked at the server. I am running on two TVs each with nVidia Shield clients.
I have also rescanned the channels and the problem is still happening daily.