New TV - Fuzzy picture - XFinity

I bought a new Samsung HD Smart TV today, brought it home, went through setup, and turned it on. The picture is fuzzy. Do I need a cable box with HDMI output to get a clearer signal?

This question, "New TV - Fuzzy picture," is about XFinity-Comcast TV television equipment.

For other news regarding New TV - Fuzzy picture, and XFinity - Comcast television equipment, see our recommended stories below.