People,
Cable leakage is a dual-edged sword. You, as a cable subscriber are responsible for everything within the home. The cable company takes care of the drop and the plant itself. If the leakage is coming from within your home, the cable company can fix it upon request, but you are also responsible for it. If you refuse to fix it, you can be disconnected.
Perhaps you should read your subscription agreements. However, if the leakage is coming from the plant, then the cable company needs to fix it and will do so because of the anomalies it causes.
The caveat is that the cable company is responsible for leakage within the entire system, and if the leakage is high enough in signal to be heard from a technician in the street with a detector, then it is high enough to be heard during an FCC leakage flyover. Yes, they fly in airplanes over the cable plant and listen for leakage. This is the reason why they make you fix leaks within your home.
Funny thing is, the FCC is most concerned with CATV leakage because of the interference it can cause to Aviation frequencies. Most leakage detectors are tuned for somewhere between 121.xxx and 125.xxx to recieve signals!
Anyway, if a technician comes to your home and says you have a leak, he or she needs to explain what that means, the charges that could be incurred, and show the user agreement that states the responsibility. I worked for quite a few years in CATV and went out of my way to explain the theory behind what I was doing and have extra copies of subscriber agreements.
So, if you have colored bars to the left side of your TV screen, shadows or ghosts, or white dots floating throughout the screen, you may have a leak somewhere!
