How to block RF interference from my digital ballast?

Just got a knock on my door from the cable guys too. I saw them outside before they came in and had the presence of mind to unplug the ballast. He said the interference was probably coming from all of the splitters and weird connections that were running around. Lots of cable wires within a few meters of my box. We don't even use the cable! Just the internet, same company. I'm not sure I want to plug the damn thing back in, and all that's in the box right now is tomatoes!
 
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