Yes, multiple transactions to EP0 per one Frame(1mSec) with CYUSB.SYS is possible. Please take the trace of USB traffic and post it here so that we can have a look at it.
Thanks for quick answer.
I'm appreciateing about Cypress's technical support.
And I'm sorry, it was not a problem caused by CYUSB.sys
I found a correct condition by UHCI-HUB.
You are welcome