Why is Roamio OTA Less Responsive than my Roku 3/4?

I'm really enjoying my Roamio OTA (with cablecard bracket and Comcast cablecard). I had been using it just for rare OTA broadcasts so it was a bit of a major overkill. Then my internet service got renewed and Comcast called to say that, while we couldn't get the same deal, we could pay just a few dollars more and get a bunch of basic cable channels. Hmm. Okay. We gave it a shot (including free HBO) and it's been really decent. The quality is not even close to OTA so I may add another basic...

Why is Roamio OTA Less Responsive than my Roku 3/4?

Why is Roamio OTA Less Responsive than my Roku 3/4?