Talk to the noise? At least a little "hello?"
no, that will anger the tiki man, instead, respond with an even louder cry of terror to prove dominance.
OT: check if it is yourself making the sound. A couple of times when I'm not saying anything, I have found myself slowly letting air out of my throat on accident, producing a strange whining sound.
Also, do you have any machinery in your house? If so, perhaps the sound could be coming from that.
It could be auditory hallucinations too, or distorted floorboard creaks.
Edit: it also could be just your stomach rumbling or a unnoticed fart.