That is the likely culprit.
Try running a fresh channel scan on your Tablo. Try to make sure that all selected channels are coming in with 5 green dots.
If not, try improving your signal by moving your antenna or try a more powerful antenna than what you have now.
If it persists, even on 5 green dots channels, don't hesitate to touch base with our support gurus. They can log in to your device to check the logs and do more investigation on the root cause: