Try running your Laptop on Battery - without Powercord, and see if Problem persists.
If solved, might be some kind of ground loop.
Try to Power your printer and Laptop from the same socket, Maybe (if possible) turn Powerplug of Laptop 180° to exchange Line and Neutral.
If problem still persists - I do not have another clue.
Edited 1 time(s). Last edit at 10/09/2017 03:44AM by Dancer.