Please provide us the following details:
Which version of the SDK are you using?.
Is your entire system working fine at High-Speed. Firmware + hardware working at USB 2.0.
Please let us know.
I was using the SDK 1.2.3 and my device do not support USB2.0. Well, strictly speaking, it enumerates itself has an empty device (nothing interesting for the host inside the descriptors) in USB 2.0 mode.
Now I just upgraded the device with SDK 1.3, and TADAAAAM : the bug seems to have completely disappeared...?! I still don't understand which point inside the release note update can affect this behavior!
Also, the SDK 1.3 corrected another bug: sometimes, the device failed enumeration at cold power-up with the previous SDK on a new Intel chipset.
I think we should share this kind of information to the community to avoid extra debugging!!!
Thank you for the post. This would be useful to others as you mentioned.