Sto provando queste righe inserite alla fine del fantomatico file built.prop
#Response -----
#Increases touch responsiveness
debug.performance.tuning=1
#Increases touch responsiveness
video.accelerate.hw=1
# Better Scrolling responsiveness and
#speed
windowsmgr.max_events_per_sec=150
ro.max.fling_velocity=20000
ro.min.fling_velocity=8000