LFO (2013) on Netflix

Plot summary

Robert Nord is an awkward man who spends his days in the basement with his synthesizers. After arguing with his wife Clara, whom he suspects of cheating, he goes back down there. Over the Internet, he tells his friends that the music Clara enjoys gives him what he calls a sound allergy. He proposes that a certain frequency could work as its opposite and bring him peace. With help from Sinus-San, an online friend, he achieves a breakthrough, though he keeps how far it goes to himself. When Simon and Linn move in next door, Robert resolves to experiment on them, despite Clara's objections.