it seems there is differences between different sticks
i test it 8GB a-data stick and it is sensed always but 2GB Kingmax SuperStick trigger to the peripheral mode and because 5v is on on vbus ( external ) this trigger pcsuite / mass storage selection menu !!!

i don't know yet why this happen
keyboard trigger a mesage something like " bogus device "
SanDisk SD card reader don't work with or without sd inserted