Unhappy [Q] How do you improve the responsiveness of the touchscreen?

I have a Vega running VegaComb 1.7 and using a USB mouse I cannot fault it it is as fast as any honeycomb tablet I've used! However, using touchscreen, takes 2 or 3 taps on some icons (mainly 3 touch buttons on bottom left of screen) and going from homescreen to homescreen is nearly impossible it's too jumpy!!

I have used the calibrate app and it doesnt improve it :( any suggestions?