Hi, I see obvious pattern that the bad ports are bus 001 and the good port is bus 003, and they are two different chips. Do you see similar correlation with chip types on other motherboards? You can see the mapping between bus numbers and controllers using ls -l /sys/bus/usb/devices/usb* Generally, with xHCI it's on the controller to packetize and schedule such transfers, so this is likey a hardware problem. Regards, Michal
