Hi,
I just ran all new RG6 quad shield cable during my house remodel (8 dedicated runs, much effort). I'm only using 4 of the runs. Now one of the cables is delivering very poor quality analog video (very pixelated). The other two runs I've been able to test are OK. I've disconnected the splitter and run directly to this room and tested a separate TV on it. Still bad (so I know it’s not the TV). Although it did get slightly better when I removed the single 1-to-4 splitter as the cable enters the house (there are no other splitters). I assume I have a problem on this one run, but one of the "good" runs also takes a similar path, so I don't think it's a problem with being near any romex, or phone wires, etc. If you're troubleshooting a single run (that you don't have full access to), where would you start? Any hope that it would be in the end connectors? That would be easy to fix, but those were pretty simple to put on, so I don't imagine the problem is there.
Thanks for any advice, -- Mark