USBHost bulk transfer times out

Hi,
I can enumerate and read the USB descriptors of a USB CDC device connected to the Arduino MKRWIF1010 and the MKR1000.

I cannot read and write to endpoints using BULK transfer.

It times out at the dispatchPkt function. I've tried the CDC, ACM and the FTDI drivers all ported to the USBHost class for the SAMD21 module.

I have tried powering the device using a splitter OTG cable or directly using an OTG while powering from a LiPoly battery. All ends up having the same frustrating timeout.

Any assistance is greatly appreciated.