More information:
As a general setup and with the above: we are streaming two concurrent stations OTA on two different Rokus. Think of it as a Picture-In-Picture on steroids. 
During the game (while we were recording), we noticed that one would simply freeze and stop working altogether, with a frame on “pause” (not moving). This happened about three times, 2 on 1 Roku and 1 on the other.
I caught another instance just now as I was at the host PC and noticed the CPU spike so thought I’d report it.
Looking at Plex the CPU is pegged in the high 90s with one of the Plex Transcoder.exe until we hit the back arrow on the Roku remote, at which point the CPU goes back to 5-10% range.
This seems to be new, as usually when there is a hitch, the spinning circle of loading death appears. In this case it simply freezes on a frame and you have to exit.
EDIT: Reported the above issue in a new thread as this seems like a different bad issue altogether:
