For a couple of years now I've been having interference issues with both analogue and digital freeview reception. On the analogue channels I get a very thin line of static flash up on all TV channels and anything else tuned in via RF. It is only about 1 or 2 mm thick and flashes up for a split second every 5 seconds or so and appears to circulate arround the TV screen. For example it will first flash at the top of the picture, then the middle, then the bottom, then just below the top, then just below the middle etc. etc. This happens most of the day, its very rare for it not to happen. I have put 2 TV's next to each other, one displaying an analogue channel and one with freeview. When this line of static flashes on the analogue channel it causes the freeview picture to break up or produce green and purple squares, also if i'm using one of the radio channels on freeview the sound makes a horrid crackle. The extent of the audio crackling or picture breaking up depends on how thick the line of interference is. This happens on all the TV's in the house and doesn't make any difference if I'm using the outdoor aerial or an indoor aerial. Any help much appreciated.