Well it's a bit of a cheat to give you a chuckle. As a German it's what I would say if I had to use a single word. Keep in mind that we don't put spaces between compound words, so it's easy to have "one word" for everything. Geräuschkulisse is a particular environment created by sound. Sendung is TV program.

In practice, I would refer to this as "ein Programm im Hintergrund anhaben" but that's more than a word.