That is a very interesting finding. I thought the external hubs would auto-configure to the highest version provided by the host. I would not expect the machine to hang or crash in that particular configuration. Do you think it is due to cheap hardware? I should read the USB spec to try to understand what is happening, but I am too lazy at the moment... Jeff
i haven't found motherboard manual on Internet, 6 usb ports are available at back panel of pc case, they look same, one is correct, one is wrong, i haven't tested with other 4
all usb devices, including those connected to external usb hub, work well within 12 hours so that i can ignore "usb 1-3: device descriptor read/64, error -71"
i bought pc in 2015 from second-hand dealer, it was old even in
2015, i am not sure if usb cabling inside case is damaged.
external usb hub is pretty new
i have tested 12.7 with both kernel 6.1.0-17 and 6.1.0-25, with
correct usb setting, both are ok after 12 hours