Your basil is just trying to get away from the sound. Mine perks up when I walk by because it knows I'm about to pick leaves for dinner. Plants probably just react to air movement or light changes from us being nearby. Still, I talk to mine too now, just in case. Can't hurt to be polite to your food.
Okay but when you say your basil "knows" you're about to pick leaves, that's the part that gets me. Like, is it just a reflex or something more? I mean idk maybe it's just me but I start overthinking if my plants are actually learning my routine. Do you do anything specific when you talk to yours, or is it just random chatting?