On Mon, 15 Oct 2018 13:49:21 -0400, Paul wrote:

My guess is, your line needs to be verified by a cable person
coming out in a truck and checking the line. And checking
that the filters are set properly for the service you're
paying for. If an analog cable TV package is part of the
"bundle" you're paying for each month, they should make it work for
you, or, explain what additional equipment is needed.

A new splitter should not make the situation worse.

Connecting it incorrectly would make the situation worse, as one example
(mixing up the input versus the outputs). Or connecting coax cables that
haven't been properly prepared. Check for proper stripping, with no
'stingers' (where a stray shield wire touches the center conductor).
Check that the connectors have been installed properly, and make sure
they're compression fittings and not screw-on, push-on, or crimp
connectors. Make sure the coax is at least RG6 Quad Shield and not RG59.
RG11 would be nice, but overkill.

Other than that, pictures of the splitter appear to indicate that it
uses a form of "push on" connections, rather than threaded connections,
and if that's true, I'd toss it directly into the trash, even if I had
to pay out of pocket for a proper unit.