Yes, they are visible. One of your upstreams is border line and all of downstream power levels are too low. Are there any splitters or attenuators on the line?
I believe there is only one splitter on the line.
Full Details on my wiring:
When I moved it to this house 2 years ago Comcast dropped a new line from the pole and connected it to me via an existing underground line. My neighbor's landscaping crew later cut that line and it had to be replaced about a year ago. So I should essentially have a new line from the pole to my house. Once inside the house it hits a splitter that is connected to a coaxial cable that is wired in my walls. The house was built in 1998 so the coax in the walls could be as old as that. I don't believe it hits any splitters from there to the modem.
There isn't a wall plate before the splitter but there is a wall plate after the splitter.
So it goes: Pole -> Splitter -> Wall Plate -> Modem
None of the cables are more than two years old except between the splitter and the wall plate.