The Comcast Cable on my TV seems to be really slow, how do I fix it?

About a week ago, out of nowhere, my Comcast Cable just started being really slow and laggy. What I mean is, if I press any buttons on my Comcast remote, it will take a 2–3 seconds to register that I even did that and it’s becoming a huge pain just to flip channels or scroll through the guide. I changed the batteries and it didn’t fix the problem. I did a couple of Google searches and couldn’t find an answer. Any help on how to fix this?