Reply to arcade buttons sensitivity

Hi to every dj ranking ers
for my first post i'd rather than speak about music but i've a problem with the arcade buttons sensitivity
compairing to the impressive ean's videos demos my buttons are way less reactive
could it comes from
1 bad soldering of the buttons?
2 standard usb cable that's not capable of transmit the midi cc fast enough?
3 Why bother anyway imitate ean, there's only one
... ?
any suggestion and advice would be useful
thanks for the support
b.