Poor Cable TV Signal

I have an issue on the same channels with poor signal and interference on both of our TVs, all of my connections are still wenched tight from when the Tech installed our service. All of the cables besides the one coming off the pole are new from the install, none of them have any damage or are near anything that would be interfering. I suspected it from the old cable on the pole that's been there since god knows when the ground cable running along the Coax holding it in place is even rusting it is that old. The issue just has gotten worse when about an extra 1/2 mile of cable was added to reach someone's house. Any advice? Anyone I should call to look into the issue? The person next-door has the same problem and called a tech for it, but he couldn't fix it when he came into the house. This has been going on for a while and only gotten worse when that extra distance was added to the run. Our internet has shown no issues on our two TVs any help?