I had a similar problem on my Acer Ferrari 4005 WLMi. I added the FingerHigh and FingerLow options to the InputDevice section as follows:
Section "InputDevice" Identifier "Synaptics Touchpad" Driver "synaptics" Option "SendCoreEvents" "true" Option "Device" "/dev/psaux" Option "Protocol" "auto-dev" Option "HorizScrollDelta" "0" Option "SHMConfig" "on" Option "FingerHigh" "40" Option "FingerLow" "20" EndSection
I had a similar problem on my Acer Ferrari 4005 WLMi. I added the FingerHigh and FingerLow options to the InputDevice section as follows:
Section "InputDevice"
Identifier "Synaptics Touchpad"
Driver "synaptics"
Option "SendCoreEvents" "true"
Option "Device" "/dev/psaux"
Option "Protocol" "auto-dev"
Option "HorizScrollDelta" "0"
Option "SHMConfig" "on"
Option "FingerHigh" "40"
Option "FingerLow" "20"
EndSection