Plex Tablo Channel: "unable to resolve video for playback"

I used to be able to play recorded content from my Amazon Fire TV’s via the Plex Tablo App but a week or two ago I started getting the “unable to resolve video for playback” error.  One day two of the three Amazon Fire TV’s would play the channel and the third one would not and now I can’t get it it to work at all… any idea?  Tablo works fine on my desktop computer.

@Jerz Does it work on another device?

@Davidvr I have three Amazon Fires and this morning the plex tablo app works on two of the three Amazon Fire TV’s and the third has the Error “unable to resolve video for playback”.  Any ideas?  All three Fire TV’s, the Tablo and my computer where the plex server resides are wired to my home network and they all are wired back to the same network switch.

EDIT:  Rebooted the third Amazon Fire TV and it is now once again working with the Tablo Plex App…  hmmm… all three are working again.  I’ll keep an eye on them but if you have any idea what might cause the video playback error I would appreciate it.

Ok… getting the error again after going from recorded tv to live tv, rebooted and get the same thing “unable to resolve video for playback”.  Let me know if there’s anything I need to do to troubleshoot.