This issue started 2-3 weeks ago and has persisted until now. Tablo recordings freeze after fast forwarding or rewinding. After I restart Roku (Settings > System > Power > Restart), the issue goes away during that viewing session and comes back the next time. I noticed this issue with other apps as well (CBS News, YouTube) occasionally but not as much as Tablo.
I have a similar problem when using the Tablo. I have communicated with Tablo quite a bit because I thought that it was a Tablo problem. When I reboot the Tablo it fixes it temporarily, but it eventually comes back.
In my case only the picture freezes, but the audio plays fine. I can rewind or fast forward through a recording but when I go to play it freezes the picture. This also happens at commercial skip and the show starts again, I only get audio and a frozen picture.