Using RS supplied PSU with RS supplied board bought 21 Oct 14. No USB (ie lsusb finds usb not initialised) with various hubs and cables. Then suddenly after 24 hours of playing it works! Mouse, kbd, SSD USB disk all running fine with an old powered hub and a brand new Maplin micro-USB to USB-A cable. Was going to try the reset button while powered next but its tricky with the big heat sink fitted. I should have drilled a hole thru it before fitting.
Checked micro USB joints on the board with a USB scope and they looked fine.
Fingers crossed for the power-up tomorrow. And the next day