I have several Dell XPS 13 machines that exhibit intermittent failures of the left USB 3.0 port, as described in this thread. I have lost data to silent corruption/disconnections on several external HDDs.
Evidence points to a hardware design flaw (insufficient shielding on a cable internally connecting the port to the controller) that causes disruption when operating at USB 3.0 protocol. Therefore, it is unlikely to be solved completely in software/firmware updates.
What I'm looking for is a software solution to forcibly downgrade a single port to use USB 2.0 even if a USB 3.0 capable device is plugged in it. Some people have reported success in using a USB 2.0 hub, but I'm looking for a solution with no extra hardware.
Windows reports the USB controller as
Intel(R) USB 3.0 eXtensible Host Controller. Both ports go through the same root hub. Please tell me if I need to supply more details regarding the controller.
There is no BIOS option to switch USB speed (as it turns out, there is, but not clearly presented). I would like the other port to operate at 3.0, if possible.