Touchpad jerks on tap, makes double clicking a pain

Question

I have a question about the touchpad in Ubuntu 13.04 on my Hp Envy 3040nr.

When I go to click tap (I don't like having to physically press the touchpad button), the cursor jerks maybe five or ten pixels in a random direction. Or, when I simply move the cursor to a location, when I release my finger from the touchpad, the cursor jumps a few pixels in a random direction.

This is a pain when I'm trying to resize windows or click small buttons especially, as a) it makes it difficult to even get on the very edge of the window to change the window size and b) even if I do, the moment I try to tap click, the cursor jumps away.

I know that in Windows, the touchpad drivers have some "forgiveness" towards very slight movement. I don't know how to emulate that on Ubuntu.

Thanks!

Answer 1

Try creating the file .xinputrc in your home folder and paste this into it:

#!/bin/sh

SYN="SynPS/2 Synaptics TouchPad"
xinput set-prop "$SYN" "Synaptics Noise Cancellation" 26 26

This doesn't totally eliminate the problem, but for me, it corrects it substantially.

Maybe type xinput list to make sure your device is called exactly "SynPS/2 Synaptics TouchPad." Set the SYN variable in the script to whatever your touchpad is named.

Answer 2

Yes, I have the same problem with my Lenovo Y480's touchpad. The sensitivity seems to be quite high and the mouse cursor jumps around making it hard to left and right click or especially double click. I've tried playing with ubuntu's system settings, the keyboard and mouse configuration app, and the pointing devices app to no avail. The best solution I've found is to enable tapping which makes left clicks much easier.

Answer 3

That's also a key problem I've got with my Lenovo L540 touchpad. CaptSaltyJack's suggestion is a step in the right direction, but it does not solve the problem completely, as the actual issue is not entirely related to the noise cancellation level.

Regarding proposed changes to ~/.xinputrc I would suggest to follow im-config's manual, so:

If you wish to create a custom configuration beyond what im-config can do for you, please copy one of these initialization code files into ~/.xinputrc or /etc/X11/xinit/xinputrc and edit it to suite your need.

Thus, if your ~/.xinputrc file exists already and it looks for example like this:

# im-config(8) generated on Fri, 29 Aug 2014 01:03:28 +0200
run_im ibus
# im-config signiture: 4218b16da65755f61e0673872943d12e  -

then you may consider to replace its contents with:

############################################################
# Paste /usr/share/im-config/data/20_ibus.rc contents HERE #
############################################################

SYN="SynPS/2 Synaptics TouchPad"
xinput set-prop "$SYN" "Synaptics Noise Cancellation" 26 26

Because ~/.xinputrc is sourced by im-config, it doesn't have to be given neither a shebang (#!/bin/sh) at the beginning nor to be executable.

If you want to verify if you changes are applied properly on startup, just check the output of:

xinput --list-props "SynPS/2 Synaptics TouchPad" | grep -i noise