Delayed Last Hitting (Missing quite a few last hits early game)

I've noticed while holding the Last Hit key in the orbwalker (through ZAIO) that it tends to be super delayed and was wondering if I should change the Attack delay lower than it's default(5)? Also if I want it to turn quicker should I increase or decrease the Turn Delay?

bump

how to fix this bump . i have been facing the same problem as well