Interference problem

HI all,
I need some advice please, I have some Polish neighbours that say I am causing them some interference, by what I can make out it's when I am on the 80m CC's as I was calling CQ on PSK63 on 20m and visited their house and there wasn't the slightest flicker or bit of noise.
I did notice though they had all their surround sound and Satellite coax all nicely taped together and there was one wire was wrapped around the bottom of the radiator in a big bunch!!

I am going to visit them again tomorrow to see what I can do, but is there any filters or ferrite's I can fit just to show I have done everything I can?

Hi Tony
I know you too, your sorting me out a power switch for my Kenpro rotator controller lol

Hopefully my neighbour will let me back in so I can sort out their wiring and so I can fit some ferrite's I have brought from the club and I'll take pictures of their wiring so you all can have a laugh

Regards
Ian
2E0GX