I have seen this multiple times on ATV4k v1. I often am watching something live, such as NFL football, when it happens, which makes it extremely frustrating.
But, after some random long period of time, the app will just disappear and return to ATV home screen. And then I need to open everything again in order to continue watching.
I submitted diagnostics the last time this happened, but I'm sure how useful they are since the bug is that the app crashes to home screen silently (there is no visible error) and need to be reopened. Diagnostics were submit immediately after reopening the app.