Dear Andy,

Yes there is still a developer's forum at
www.usb.org but I thought it was a more proper question for this forum than for a usb forum, because I can guess by looking in the USB analyser traces that the problem is in the W81E381AD uC (or in my firmware of course) not in the USB protocol.

Anyway I will post my question there too because perhaps some developer has used that micro.
If I finally get a solution I will post it here too.

Thank you.

Xavi