A cheap set may actually work better BUT I got a feelin you will see
it on anything since you know about it.
You could try tracking down the source. Turn off all house breakers
except the one the TV is on. If it goes away turn them on one at a
time til it comes back. Then you know the line & can unplug things.
If you cant get rid if it turn the breakers back off & walk around with
an AM radio listening for hot spots. Remember it can be something on batteries
causing it. OH watch for loose cables on other things in the house.
good luck Zeno
LFOD !