Comment 203 for bug 88746

FYI: I've filed a wishlist bug about automatic fallback to usb 1.1 if 2.0 doesn't work. In that way you won't manually have to unload ehci-hcd, so it could be some sort of workaround for your problem here (at least for most of you) You can look at https://bugs.launchpad.net/ubuntu/+source/linux-meta/+bug/177430 if you're interested.

It worked equally bad for me with Hardy alpha2, but as I said I think my problem is bad internal cabling.