The Stuttering Pointer
Power management on Linux laptops is notoriously strict. To squeeze every minute out of the battery, Ubuntu frequently utilizes a feature called USB auto-suspend. If you are using a wired USB mouse (or the wireless dongle for a mouse) and you do not move it for a few seconds—perhaps while reading a long web page—Ubuntu automatically cuts power to that specific USB port. The moment you touch the mouse again, there is a severe, noticeable delay (stutter or lag) while the system repowers the port, re-initializes the hardware, and finally registers the movement.
Keeping the Mouse Awake
To ensure a perfectly smooth, instantaneous response from your pointer and stop Ubuntu from automatically suspending your USB mouse, you must blacklist the mouse from the auto-suspend power rules.
The most permanent fix involves modifying the GRUB bootloader parameters to disable USB auto-suspend globally. Open your terminal (Ctrl+Alt+T) and type: sudo nano /etc/default/grub. Look for the specific line that starts with GRUB_CMDLINE_LINUX_DEFAULT=. It will likely contain parameters like “quiet splash”. You need to add a command to the end of this string, inside the quotation marks. Modify the line so it looks like this: GRUB_CMDLINE_LINUX_DEFAULT="quiet splash usbcore.autosuspend=-1". Press Ctrl+O to save the file, hit Enter to confirm, and then press Ctrl+X to exit the Nano editor. Finally, you must update the bootloader for the new kernel parameter to take effect by running: sudo update-grub. Reboot your machine, and your USB ports will now remain fully powered at all times.