Hard to tell without knowing anything about the dog. I know some people use a clicker so anytime something clicks they thing they are either in trouble, or getting a treat for being good, just depends on how they trained the dog.

It could also just be a weird quirk, like my dogs will howl at sirens. It don't matter if it's noon or midnight, if there is a siren, they howl.

imgur wrote He has PTSD and you're scaring the shit out of him.

This is why.
You need to turn your phone down.
Or he's going to jump on you 1 day.