I've a friend who has nothing but IKEA TRÅDFRI lightbulbs. Each and every one of these has a subtle coil whine, and stepping into his home is like stepping into a rainforest, but unpleasant. He doesn't hear a single peep from them, but to me it's hella grating. The noise changes depending on what light it's emitting, as well as the brightness. The worst is when the light is off.