Others have had problems with signal strength after moving to the 4 tuner. I would start with antenna location, position and signal going into the Tablo.
Had an on-going problem and can’t seem to find help. Support finally sent me a new Tablo but that didn’t resolve the issue, so here goes:
I have a Roku 4 which works great with everything but Tablo, a great antenna hard-wired into the Tablo, a Samsung Smart TV. The antenna is not the issue because if I use HDMI to watch a program through Roku/Tablo, it is pixelated and reception is horrible. So switch to TV setting on Smart TV, not HDMI and watch the same program live on TV, the reception is…