Where is this sound coming from?

I am on day three of my quarantine, & let me tell you, this is not a drill, this is a for-real quarantine, and I am not practicing social distancing, it’s much more than that.

I was exposed to the coronavirus at work last week, and since all of us found out, all the people at my work went into total isolation, however at first it was mostly fun, kind of exciting, but being totally alone is starting to get to me. Am I going insane, or is this what it’s love to be so bored & have no option? Last night I thought I heard voices come from the air vent in my kitchen. I jumped up on my bed, being so careful & quiet, & put my ear right up against the air vent. I am sure I heard someone talking although it sounded actually far away, from deep within the HVAC duct, however the next day I turned off the A/C & listened once more, & I must have stood there for a minute or so. I went to other air vents throughout the house, spending a couple of minutes at each a single, but all was quiet. I ran the cooling system like normal for the rest of the day, however I would turn it off from time to time to see if there were any other odd noises, then late the next night I heard it again, the same voice, coming from the same air vent. Now I have to pick if my Heating & Air Conditioning plan is haunted, if I’m going crazy, or if maybe I have the virus!

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