We have a similar issue to deal with. Many of our relatives have a TV, and I tell them in advance, please have us over at a time that you will not be missing a “must see” show. Usually, this ends up being Shabbos / Tomtov, but at least they know where we stand.
Reading material? That doesnt scream out to you like the tube, so I can (pretty much) rely on my kids leaving well enough alone