I have the same problem on only one of four computers running Ubuntu 8.04 Hardy and 8.10 Intrepid. The problem has existed since at least Hardy and seems to affect only certain motherboards. It is associated with the ehci_hcd USB2.0 controller in the kernel.
I haven't found a solution yet, but one way round it is to disable the onboard USB2.0 controller in the BIOS. Alternatively run the code
Code:
sudo modprobe -r ehci_hcd
which will remove the USB2.0 controller from the kernel.
The down side to both these fixes is that USB interfaces will be only USB 1.0/1.1, which will make transfers from large mass storage devices very slow indeed.
I have spent hours reading post and bug reports, but the development team do not seem to acknowledge this a a valid bug.
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