I unplugged it for 30 seconds, restarted. Seems top be the only thing that works for me. Based on my experience as a developer, and the following occasional symptoms, there seems to be objects that are not released after a process, or a memory leak in the app/device.
- Thumb nails disappear.
- Roku freezes.
- Roku stops reacting to the remote.
- Roku reboots on it's own.
The only solution for me is to unplug, wait 30sec & plug it back in.