As I get older, I hear ghost knocking more often.
We moved a few years ago & the ghost knocking got worse.
The wife & I both see what looks like a person or shadow of one fliting past doorways in the corner of our eyes.
Over night guests are told not to worry, we know it / they are here.
Sure would like a good look though.
This sounds plausible. Woodpeckers will do that.
that’s more like a Sheldon knock.
And I’m sure they sleep just fine, once they’re told “It’s okay, we know the place is haunted.”
Damn, now I want to put in a few odd noise-making devices if I ever remodel a house… “Oh, that? Ghosts. Pay them no mind, they never do any harm, and they hardly ever steal anything or move all your stuff around. Be careful you don’t leave your toothbrush out, though…”
I don’t think I’d get many repeat visitors.
Get a wireless camera like these ones (look for audio recording too):
http://www.amazon.com/Best-Sellers-Camera-Photo-Surveillance-Security-Cameras/zgbs/photo/898400
Point the camera to the suspected area.
Set a computer to record the stream.
After an incident check the recorded video.
Nah, I have a game camera but it is more fun to just be able to talk about it. We are retired, need some talking points sometimes.
And all my family & friends are loving help us watch for it.
Prolly not for real because the cats & dog never seem to see it or else it is not worth looking or barking about.
The old house had a lady in white robe we would see sometimes late at night.
Maybe it is some kind of mass hysteria we are passing back & forth between just us two.
Hummmmmmmmmmmmmmm Need to read up on that.
The mystery of the dog that didn’t bark? That just confirms that the perp is somebody well-known to the dog. Sherlock Holmes understood that.
Or it’s a picture frame.
I can’t believe I forgot that…
It’s never the picture frame. 
who framed the picture?
Had an unexplained knocking a few months ago that I described as a “stereotype knock”. Each time it happened I heard, “knock, knock, knock”. It was really starting to freak me out, then I figured out what it was.
the default notification for a new message in WhatsApp. My brother would occasionally message me. I would eventually see my phone blinking and check. I didn’t realize there was a sound for new message, and my phone lives on the kitchen island by a recharge outlet.
Beetles that make a knocking sound, which can be amplified by the layout of some houses, traditionally associated with the supernatural …