It starts to make kind of weird noise at 9-10mm excursion

i thought it would do more.. i have purifi's Chinese clone which is deadsilent at 10mm xmax....... even at 11-13mm quite silent FREE AIR.....
Like why the fux is epiques xmax excursion destroyed by a chinese clone driver of purifi?? As it is epiques whole selling point....
Thats why i bought opal1, but disappointed now....