I am using a USB-HUB-AG7 with a Raspberry Pi. After about a minute, the Raspberry Pi disconnects from the hub. Nothing attached to the hub - it is only supplying power to the Pi. Snippet from dmesg:
[217615.810565] usb 1-1.3: Product: USB 2.0 Hub [Safe]
[217615.817118] hub 1-1.3:1.0: USB hub found
[217615.818047] hub 1-1.3:1.0: 7 ports detected
[217692.327418] usb 1-1.3: reset full-speed USB device number 4 using dwc_otg
[217692.407383] usb 1-1.3: device descriptor read/64, error -32
[217692.597409] usb 1-1.3: device descriptor read/64, error -32
[217692.787445] usb 1-1.3: reset full-speed USB device number 4 using dwc_otg
[217692.867448] usb 1-1.3: device descriptor read/64, error -32
[217693.057349] usb 1-1.3: device descriptor read/64, error -32
[217693.247376] usb 1-1.3: reset full-speed USB device number 4 using dwc_otg
[217693.667217] usb 1-1.3: device not accepting address 4, error -32
[217693.747445] usb 1-1.3: reset full-speed USB device number 4 using dwc_otg
[217694.167221] usb 1-1.3: device not accepting address 4, error -32
[217694.277249] hub 1-1.3:1.0: activate --> -19
[217694.277520] usb 1-1.3: USB disconnect, device number 4
Very repeatable. Again, no peripherals are plugged into hub. Any ideas?