FTDI FT4232H baudrate

[idanuliel]

I'm using FT4232H to read and write registers over spi and I noticed a major performance difference when using windows and Linux.
For my test, I'm reading 32-bit register 2048 times when the spi is configured to 10e6 clock using lib USB 1.2.6 and 1.2.7.3 for windows and libusb 1.0 for Linux bout machines have roughly the same processor memory python version etc.

in windows the execution time is ~6 seconds and in Linux its ~0.6 seconds (!)

I know that the FTDI is recognized as rs232 under the device manager in windows but i can't see an option to configure the baudrate or any other property that can explain the performance gap.

Any suggestion on how I can improve the read speed under windows?