Veja o HorizHysteresis
e VertHysteresis
do synclient. Veja o que eles fazem de acordo com man synaptics
.
Option "HorizHysteresis" "integer"
The minimum horizontal HW distance required to generate motion events. Can be specified as a
percentage. Increase if noise motion is a problem for you. Zero is disabled. Default: 0.5 per‐
cent of the diagonal or (in case of evdev) the appropriate "fuzz" as advertised by the device.
Option "VertHysteresis" "integer"
The minimum vertical HW distance required to generate motion events. See HorizHysteresis.