Spooky, but not uncommon.
When your mouse acts up, it can be really frustrating, if not downright spooky.
Fortunately there are several mundane potential causes.
Let’s look at a few.
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Mouse is moving on its own
For the mouse itself, clean it, replace the batteries, check the cable, make sure there’s no radio interference. Check the connections, and mouse settings, and make sure you’re not brushing against any touchpad. A good, quick, diagnostic tool is to try using a different mouse for a while to see if the problem persists.
Clean the mouse & surface
Dirt can easily cause the mouse to misbehave. That applies to both the sensor underneath the mouse itself, but also the surface on which you happen to have the mouse. Make sure that both are clean and free of dust and debris.
I find myself needing to clean the Corgi hair every couple of weeks or so.
Check for interference
If using a wireless mouse, it’s not terribly uncommon that radio interference could cause some confusion. The thing to look for is a short, clear path between the mouse and its receiver, or your machine (if you’re using Bluetooth) and no powerful electronic devices between.
Replace the batteries
While most mice just stop working completely when their batteries die, some will work sporadically or downright misbehave.
The fix is easy: replace them and see if things improve.
Check the cable
There are two parts to this: the cable itself and the socket you have it plugged into.
A quick test is to wiggle the cable where it joins the mouse and back at the connector. If that causes activity, then the cable is probably bad. Be sure to look for damage along the entire length of the cable as well.
Try also plugging the mouse into a different USB port, or directly into your computer if you normally have it plugged into a hub. Sometimes a socket or plug will go bad or accumulate enough dust and dirt to make the connection intermittent.
Swap the mouse
If you have a chance, swap your mouse with another. I have a small graveyard of old mice that I hang onto for just this purpose. They all work, they’re just old and dirty, but they come in very handy to determine if a problem I’m seeing is my current mouse or something else.
Watch your touch
Honestly, a large number of these “my mouse is moving” scenarios turn out to be the trackpad on a laptop. Either of two things generally happens:
- The trackpad itself is super sensitive, even to dirt and dust.
- You’re touching it as you move your hands without realizing it.
Most trackpads can be turned off, so that’s a great first step to diagnose.
It is worth checking your settings as well.
Items to look for in the Settings app for Mouse settings are things like “sensitivity” or “pointer speed”. Review the button assignments to make sure that they’re correct as well.
Mouse move options like “snap to” will cause the mouse to move to specific points under certain conditions. These options can easily confuse if you’re not prepared for them, so make sure they’re what you want or turn them off.
When people see the mouse pointer move on its own it’s not uncommon for them to think that someone else is controlling their machine.
This is rarely the case. Possible, but very rare.
To begin with, someone with truly malicious intent will be trying to avoid detection, so they’ll either use software that doesn’t move the mouse pointer, or they’ll just be avoiding the mouse altogether.
Second, while remote access software does indeed allow someone to control your machine remotely, including moving the mouse, you’ll have had to have let them in. In other words, you’ll know that this is what’s happening, because you’re the one that set it up.
Don’t panic. Take some reasonable diagnostic steps, as outlined above, and you’ll be able to at least narrow down the cause. Nine times out of ten, it’ll be the mouse itself.
That’s why it’s always handy to have a spare.
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