>>Run it straight from a cable outlet. >>
This is what may have to be done. I took the high quality splitter where the main line from the street is connected to next door, off. I put that into this 6 way connector metal tablet that is wired into the whole house.
I put the cable from the street, into the 'In' connection. I re-wired everything else, including the wire that goes to our side of the house, into the out connection. I left everything on our side of the house alone.
However, when I took the high quality splitter over to the cable modem, and hooked everything up, it STILL didn't work. I waited a few minutes for all the lights to light up, nothing. I unhooked it, put the one directly from the wall outlet in, worked perfectly.
We have an extra large wire ready...if I new how to properly wire it, I'd do it myself in a little under an hour. Heh, although that's probably not a good idea. When we brought the wire over to this side of the house through the attic, I Accidentally stepped off the hard wood and onto the soft portion with the sheeting, and my foot fell through the floor

...
Looks like a situation to be resolved for the weekend when the parents get down..