EDIT:  I THINK I FIGURED THE PROBLEM.



I had two UPS battery backups on the same circuit.  Maybe one was bad, or somehow the two of them together created an interference pattern.  I removed one the UPS backups and the Wacom settled down again.

Now if I could just figure out why the Wacom driver keeps disappearing every time I restart my computer.  I have to reinstall the drivers every time!












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Original OP

My Wacom pen/tablet started jittering and quivering a few weeks ago.



It seemed to start shaking when I added a wireless mouse?   I have tried disconnecting the mouse and going back to a wired mouse but no change to the pen quivering.  I received an error message the day I installed the mouse about "AppleUSBEthernetHost.kext" - not sure if that's related?

I have tried disconnecting lights and speakers, looking for bad grounds, big motors, and RF interference.  No luck there.




Anybody had experience with this?  How did you solve it?

Have you tried a clean install of your tablet driver?

Hi Rinaldi,

I have uninstalled and reinstalled the mouse driver and the wacom driver.

I also tried installing older legacy drivers, but no improvement

Tried different usb ports.




Wacom pen is still shivering.



I will try installing the tablet on another computer to see if there is any difference.

If it's a software problem maybe this tutorial will help you - youtube.com/watch?v=b_BYCcX0CuM
It helped me a great deal, though my problem was the one mentioned in the title
But you might as well give it a shot

Does your Wacom have a Touch feature? If so turn that off and check if it still happens.

Something similar happened to me recently. I placed my mobile phone on my tablet accidentally and my mouse pointer started going crazy! It went all over my screen as if someone else was controlling it. So a wireless signal definitely affects it somehow. I switched my Touch feature off and kept my phone well away from the tablet and now it never happens.

Weird.

Have you checked the nib on your pen?  My pen starts acting strangely if the nib is worn.  Just another place to check!

:)PJ

Interesting test results.



I installed the tablet on a different computer with no peripherals.  The shaking is gone.  Installation of additional devices - USB external hard drive, second monitor, etc made the pen start quivering slightly.

The twitchiness really begins when I bring my hand close to the tablet.

Maybe I need to wear a grounding strap?
Some sort of RF shielding- wrap the pen in a lead blanket?
Lay off the caffeine?